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Results from the 2008
National Survey on Drug Use and Health:
National Findings

 

 

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Substance Abuse and Mental Health Services Administration
Office of Applied Studies

Acknowledgments

This report was prepared by the Office of Applied Studies (OAS), Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services (HHS), and by RTI International (a trade name of Research Triangle Institute), Research Triangle Park, North Carolina. Work by RTI was performed under Contract No. 283-2004-00022.

Public Domain Notice

All material appearing in this report is in the public domain and may be reproduced or copied without permission from SAMHSA. Citation of the source is appreciated. However, this publication may not be reproduced or distributed for a fee without the specific, written authorization of the Office of Communications, SAMHSA, HHS.

Recommended Citation

Substance Abuse and Mental Health Services Administration. (2009). Results from the 2008 National Survey on Drug Use and Health: National Findings (Office of Applied Studies, NSDUH Series H-36, HHS Publication No. SMA 09-4434). Rockville, MD.

Electronic Access and Copies of Publication

This publication may be downloaded from http://www.oas.samhsa.gov. Hard copies may be obtained from http://www.oas.samhsa.gov/copies.cfm. Or please call SAMHSA's Health Information Network at 1-877-SAMHSA-7 (1-877-726-4727) (English and Español).

Originating Office

Substance Abuse and Mental Health Services Administration
Office of Applied Studies
Division of Population Surveys
1 Choke Cherry Road, Room 7-1044
Rockville, MD 20857

September 2009

Table of Contents

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List of Figures
List of Tables
Revised Adult Mental Illness Estimates for 2008 to 2011

Highlights

1. Introduction
1.1. Summary of NSDUH
1.2. Limitations on Trend Measurement
1.3. New Data on Mental Health
1.4. Format of Report and Explanation of Tables
1.5. Other NSDUH Reports and Data

2. Illicit Drug Use
Age
Youths Aged 12 to 17
Young Adults Aged 18 to 25
Adults Aged 26 or Older
Gender
Pregnant Women
Race/Ethnicity
Education
College Students
Employment
Geographic Area
Criminal Justice Populations
Frequency of Use
Association with Cigarette and Alcohol Use
Driving Under the Influence of Illicit Drugs
Source of Prescription Drugs

3. Alcohol Use
3.1. Alcohol Use among Persons Aged 12 or Older
Age
Gender
Pregnant Women
Race/Ethnicity
Education
College Students
Employment
Geographic Area
Association with Illicit Drug and Tobacco Use
Driving Under the Influence of Alcohol
3.2. Underage Alcohol Use

4. Tobacco Use
Age
Gender
Pregnant Women
Race/Ethnicity
Education
College Students
Employment
Geographic Area
Association with Illicit Drug and Alcohol Use
Frequency of Cigarette Use

5. Initiation of Substance Use
Initiation of Illicit Drug Use
Comparison, by Drug
Marijuana
Cocaine
Heroin
Hallucinogens
Inhalants
Psychotherapeutics
Alcohol
Tobacco

6. Youth Prevention-Related Measures
Perceptions of Risk
Perceived Availability
Perceived Parental Disapproval of Substance Use
Feelings about Peer Substance Use
Fighting and Delinquent Behavior
Religious Beliefs and Participation in Activities
Exposure to Substance Use Prevention Messages and Programs
Parental Involvement

7. Substance Dependence, Abuse, and Treatment
7.1. Substance Dependence or Abuse
Age at First Use
Age
Gender
Race/Ethnicity
Education/Employment
Criminal Justice Populations
Geographic Area
7.2. Past Year Treatment for a Substance Use Problem
7.3. Need for and Receipt of Specialty Treatment
Illicit Drug or Alcohol Use Treatment and Treatment Need
Illicit Drug Use Treatment and Treatment Need
Alcohol Use Treatment and Treatment Need

8. Mental Health
Serious Mental Illness
Serious Psychological Distress
Suicidal Thoughts and Behavior
Major Depressive Episode (Depression)
Comparing the Measures
Mental Health Service Utilization
8.1. Adults Aged 18 or Older
Prevalence of Serious Mental Illness among Adults
Mental Health Service Use among Adults with Serious Mental Illness
Serious Mental Illness and Substance Use and Dependence or Abuse among Adults
Mental Health Care among Adults with Co-Occurring Serious Mental Illness and Substance Use Disorders
Prevalence of Suicidal Thoughts and Behavior among Adults
Prevalence of Major Depressive Episode among Adults
Major Depressive Episode and Substance Use and Dependence or Abuse among Adults
Treatment for Major Depressive Episode among Adults
Prevalence of Past 30 Day Serious Psychological Distress among Adults
Serious Psychological Distress and Substance Use among Adults
Mental Health Service Use and Unmet Need for Mental Health Care among Adults
8.2. Youths Aged 12 to 17
Prevalence of Major Depressive Episode among Youths
Major Depressive Episode and Substance Use among Youths
Treatment for Major Depressive Episode among Youths
Mental Health Service Use among Youths

9. Discussion of Trends in Substance Use among Youths and Young Adults

Appendix

A. Description of the Survey
B. Statistical Methods and Measurement
C. Key Definitions, 2008
D. Other Sources of Data
E. References
F. Sample Size and Population Tables
G. Selected Prevalence Tables
H. List of Contributors

List of Figures

2.1 Past Month Illicit Drug Use among Persons Aged 12 or Older: 2008

2.2 Past Month Use of Selected Illicit Drugs among Persons Aged 12 or Older: 2002-2008

2.3 Past Month Nonmedical Use of Types of Psychotherapeutic Drugs among Persons Aged 12 or Older: 2002-2008

2.4 Past Month Illicit Drug Use among Persons Aged 12 or Older, by Age: 2008

2.5 Past Month Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

2.6 Past Month Use of Selected Illicit Drugs among Young Adults Aged 18 to 25: 2002-2008

2.7 Past Month Illicit Drug Use among Adults Aged 50 to 59: 2002-2008

2.8 Past Month Marijuana Use among Youths Aged 12 to 17, by Gender: 2002-2008

2.9 Past Month Illicit Drug Use among Persons Aged 12 or Older, by Race/Ethnicity: 2008

2.10 Past Month Illicit Drug Use among Persons Aged 18 or Older, by Employment Status: 2007 and 2008

2.11 Past Month Illicit Drug Use among Persons Aged 12 or Older, by County Type: 2008

3.1 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 or Older, by Age: 2008

3.2 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 or Older, by Race/Ethnicity: 2008

3.3 Heavy Alcohol Use among Adults Aged 18 to 22, by College Enrollment: 2002-2008

3.4 Driving Under the Influence of Alcohol in the Past Year among Persons Aged 12 or Older: 2002-2008

3.5 Driving Under the Influence of Alcohol in the Past Year among Persons Aged 16 or Older, by Age: 2008

3.6 Current Alcohol Use among Persons Aged 12 to 20, by Age: 2002-2008

3.7 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 to 20, by Gender: 2008

4.1 Past Month Tobacco Use among Persons Aged 12 or Older: 2002-2008

4.2 Past Month Tobacco Use among Youths Aged 12 to 17: 2002-2008

4.3 Past Month Cigarette Use among Persons Aged 12 or Older, by Age: 2008

4.4 Past Month Cigarette Use among Youths Aged 12 to 17, by Gender: 2002-2008

4.5 Past Month Cigarette Use among Women Aged 15 to 44, by Pregnancy Status: Combined Years 2002-2003 to 2007-2008

4.6 Past Month Tobacco Use among Adults Aged 18 or Older, by Education: 2008

5.1 Specific Drug Used When Initiating Illicit Drug Use among Past Year Initiates of Illicit Drugs Aged 12 or Older: 2008

5.2 Past Year Initiates for Specific Illicit Drugs among Persons Aged 12 or Older: 2008

5.3 Mean Age at First Use for Specific Illicit Drugs among Past Year Initiates Aged 12 to 49: 2008

5.4 Past Year Marijuana Initiates among Persons Aged 12 or Older and Mean Age at First Use of Marijuana among Past Year Marijuana Initiates Aged 12 to 49: 2002-2008

5.5 Past Year Hallucinogen Initiates among Persons Aged 12 or Older: 2002-2008

5.6 Past Year Methamphetamine Initiates among Persons Aged 12 or Older and Mean Age at First Use of Methamphetamine among Past Year Methamphetamine Initiates Aged 12 to 49: 2002-2008

5.7 Past Year Cigarette Initiates among Persons Aged 12 or Older, by Age at First Use: 2002-2008

5.8 Past Year Cigarette Initiation among Youths Aged 12 to 17 Who Had Never Smoked Prior to the Past Year, by Gender: 2002-2008

6.1 Past Month Binge Drinking and Marijuana Use among Youths Aged 12 to 17, by Perceptions of Risk: 2008

6.2 Perceived Great Risk of Cigarette and Alcohol Use among Youths Aged 12 to 17: 2002-2008

6.3 Perceived Great Risk of Marijuana Use among Youths Aged 12 to 17: 2002-2008

6.4 Perceived Great Risk of Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

6.5 Perceived Availability of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

6.6 Approached in the Past Month by Someone Selling Drugs among Youths Aged 12 to 17: 2002-2008

6.7 Exposure to Substance Use Prevention Messages and Programs among Youths Aged 12 to 17: 2002-2008

7.1 Substance Dependence or Abuse in the Past Year among Persons Aged 12 or Older: 2002-2008

7.2 Dependence on or Abuse of Specific Illicit Drugs in the Past Year among Persons Aged 12 or Older: 2008

7.3 Dependence on or Abuse of Illicit Drugs, Marijuana, Cocaine, and Pain Relievers in the Past Year among Persons Aged 12 or Older: 2002-2008

7.4 Alcohol Dependence or Abuse in the Past Year among Adults Aged 21 or Older, by Age at First Use of Alcohol: 2008

7.5 Dependence on or Abuse of Alcohol and Illicit Drugs among Youths Aged 12 to 17: 2002-2008

7.6 Substance Dependence or Abuse in the Past Year, by Age and Gender: 2008

7.7 Locations Where Past Year Substance Use Treatment Was Received among Persons Aged 12 or Older: 2008

7.8 Substances for Which Most Recent Treatment Was Received in the Past Year among Persons Aged 12 or Older: 2008

7.9 Received Most Recent Treatment in the Past Year for the Use of Pain Relievers among Persons Aged 12 or Older: 2002-2008

7.10 Past Year Perceived Need for and Effort Made to Receive Specialty Treatment among Persons Aged 12 or Older Needing But Not Receiving Treatment for Illicit Drug or Alcohol Use: 2008

7.11 Reasons for Not Receiving Substance Use Treatment among Persons Aged 12 or Older Who Needed and Made an Effort to Get Treatment But Did Not Receive Treatment and Felt They Needed Treatment: 2005-2008 Combined

8.1 Serious Mental Illness in the Past Year among Adults Aged 18 or Older, by Age and Gender: 2008

8.2 Number of Types of Mental Health Services Received in the Past Year among Persons Aged 18 or Older with Past Year Serious Mental Illness Who Received Mental Health Services in the Past Year: 2008

8.3 Past Year Mental Health Care and Treatment for Substance Use Problems among Adults Aged 18 or Older with Both Serious Mental Illness and a Substance Use Disorder: 2008

8.4 Suicidal Thoughts in the Past Year among Adults Aged 18 or Older, by Age and Gender: 2008

8.5 Suicidal Thoughts and Behavior in the Past Year among Adults Aged 18 or Older: 2008

8.6 Major Depressive Episode in the Past Year among Adults Aged 18 or Older, by Severe Impairment, Age, and Gender: 2008

8.7 Substance Dependence or Abuse among Adults Aged 18 or Older, by Major Depressive Episode in the Past Year: 2008

8.8 Past Year Mental Health Service Use among Adults Aged 18 or Older, by Type of Care: 2002-2008

8.9 Reasons for Not Receiving Mental Health Services in the Past Year among Adults Aged 18 or Older with an Unmet Need for Mental Health Care Who Did Not Receive Mental Health Services: 2008

8.10 Major Depressive Episode in the Past Year among Youths Aged 12 to 17, by Severe Impairment, Age, and Gender: 2008

8.11 Substance Use among Youths Aged 12 to 17, by Major Depressive Episode in the Past Year: 2008

8.12 Past Year Mental Health Service Use among Youths Aged 12 to 17, by Gender: 2008

8.13 Number of Outpatient Visits in the Past Year among Youths Aged 12 to 17 Who Received Outpatient Specialty Mental Health Services: 2008

9.1 Past Year Ecstasy and LSD Use among Youths in NSDUH and MTF: 2002-2008

9.2 Past Month Marijuana Use among Youths in NSDUH, MTF, and YRBS: 1971-2008

B.1 Required Effective Sample as a Function of the Proportion Estimated

B.2 Structure of Mental Health Surveillance Study Sampling Design

List of Tables

9.1 Comparison of NSDUH and MTF Prevalence Estimates among Youths: Percentages, 2002-2008

9.2 Comparison of NSDUH and MTF Prevalence Estimates among Young Adults: Percentages, 2002-2008

B.1 Demographic and Geographic Domains Forced to Match Their Respective U.S. Census Bureau Population Estimates through the Weight Calibration Process, 2008

B.2 Summary of 2008 NSDUH Suppression Rules

B.3 Weighted Percentages and Sample Sizes for 2007 and 2008 NSDUHs, by Final Screening Result Code

B.4 Weighted Percentages and Sample Sizes for 2007 and 2008 NSDUHs, by Final Interview Code

B.5 Response Rates and Sample Sizes for 2007 and 2008 NSDUHs, by Demographic Characteristics

B.6 Kappa Statistics for Selected Substance Use, Substance Use Treatment, and Mental Health Variables: 2006 NSDUH Reliability Study

B.7 Selected Mental Health Measures among Persons Aged 18 or Older, by Survey Year and Scale: Percentages

B.8 Past Year K6 Item Response Distributions, by Survey Year and Scale: Percentages

B.9 Major Depressive Episode Status among Persons Aged 18 or Older, by Key Demographics and Survey Year and Scale: Percentages

B.10 Mental Health Surveillance Study Sample Allocation (n = 1,500)

B.11 Mental Health Surveillance Study Agreement and Completion Response Rates, by K6 Score (Unweighted and Weighted)

B.12 Response Rates (Unweighted and Weighted), by K6 Score Category

B.13 Final WHODAS and SDS Models

B.14 Final ROC Statistics of Final WHODAS Model: Weighted Numbers in Thousands

B.15 Final ROC Statistics of Final SDS Model: Weighted Numbers in Thousands

B.16 K6 Cut Points for Each WHODAS and SDS Total Score

D.1 Use of Specific Substances in Lifetime, Past Year, and Past Month among 8th, 10th, and 12th Graders in NSDUH and MTF: Percentages, 2007 and 2008

D.2 Lifetime and Past Month Substance Use among Students in Grades 9 to 12 in YRBS and NSDUH: Percentages, 2005 and 2007

F.1 Survey Sample Size for Respondents Aged 12 or Older, by Gender and Detailed Age Category: 2007 and 2008

F.2 Numbers (in Thousands) of Persons Aged 12 or Older, by Gender and Detailed Age Category: 2007 and 2008

F.3 Survey Sample Size for Respondents Aged 12 or Older, by Age Group and Demographic Characteristics: 2007 and 2008

F.4 Numbers (in Thousands) of Persons Aged 12 or Older, by Age Group and Demographic Characteristics: 2007 and 2008

F.5 Survey Sample Size for Respondents Aged 12 or Older, by Age Group and Geographic Characteristics: 2007 and 2008

F.6 Numbers (in Thousands) of Persons Aged 12 or Older, by Age Group and Geographic Characteristics: 2007 and 2008

G.1 Types of Illicit Drug Use in Lifetime among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.2 Types of Illicit Drug Use in Lifetime among Persons Aged 12 or Older: Percentages, 2002-2008

G.3 Types of Illicit Drug Use in the Past Year among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.4 Types of Illicit Drug Use in the Past Year among Persons Aged 12 or Older: Percentages, 2002-2008

G.5 Types of Illicit Drug Use in the Past Month among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.6 Types of Illicit Drug Use in the Past Month among Persons Aged 12 or Older: Percentages, 2002-2008

G.7 Types of Illicit Drug Use in the Past Month among Persons Aged 12 to 17: Percentages, 2002-2008

G.8 Types of Illicit Drug Use in the Past Month among Persons Aged 18 to 25: Percentages, 2002-2008

G.9 Types of Illicit Drug Use in the Past Month among Persons Aged 26 or Older: Percentages, 2002-2008

G.10 Illicit Drug Use in Lifetime, Past Year, and Past Month, by Detailed Age Category: Percentages, 2007 and 2008

G.11 Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 12 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.12 Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 12 to 17, by Demographic Characteristics: Percentages, 2007 and 2008

G.13 Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 18 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.14 Tobacco Product and Alcohol Use in the Past Month among Persons Aged 12 or Older, by Gender: Numbers in Thousands, 2002-2008

G.15 Tobacco Product and Alcohol Use in the Past Month among Persons Aged 12 or Older, by Gender: Percentages, 2002-2008

G.16 Tobacco Product and Alcohol Use in the Past Month among Persons Aged 12 to 17, by Gender: Percentages, 2002-2008

G.17 Tobacco Product and Alcohol Use in the Past Month among Persons Aged 18 to 25, by Gender: Percentages, 2002-2008

G.18 Tobacco Product and Alcohol Use in the Past Month among Persons Aged 26 or Older, by Gender: Percentages, 2002-2008

G.19 Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 12 to 20, by Gender: Percentages, 2002-2008

G.20 Alcohol Use, Binge Alcohol Use, and Heavy Alcohol Use in the Past Month, by Detailed Age Category: Percentages, 2007 and 2008

G.21 Alcohol Use, Binge Alcohol Use, and Heavy Alcohol Use in the Past Month among Persons Aged 12 to 20, by Demographic Characteristics: Percentages, 2007 and 2008

G.22 Cigarette Use in Lifetime, Past Year, and Past Month, by Detailed Age Category: Percentages, 2007 and 2008

G.23 Cigarette Use in Lifetime, Past Year, and Past Month among Persons Aged 12 to 17, by Demographic Characteristics: Percentages, 2007 and 2008

G.24 Cigarette Use in Lifetime, Past Year, and Past Month among Persons Aged 18 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.25 Perceived Risk and Availability of Substances among Persons Aged 12 to 17: Percentages, 2002-2008

G.26 Past Year Initiation of Substance Use among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.27 Substance Dependence or Abuse for Specific Substances in the Past Year among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.28 Substance Dependence or Abuse for Specific Substances in the Past Year among Persons Aged 12 or Older: Percentages, 2002-2008

G.29 Substance Dependence or Abuse in the Past Year among Persons Aged 12 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.30 Received Substance Use Treatment at Any Treatment Location or at a Specialty Facility in the Past Year among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.31 Received Substance Use Treatment at Any Treatment Location or at a Specialty Facility in the Past Year among Persons Aged 12 or Older: Percentages, 2002-2008

G.32 Needed and Received Treatment for a Substance Use Problem in the Past Year among Persons Aged 12 or Older: Numbers in Thousands, 2002-2008

G.33 Needed and Received Treatment for a Substance Use Problem in the Past Year among Persons Aged 12 or Older: Percentages, 2002-2008

G.34 Needed and Received Treatment at a Specialty Facility for an Illicit Drug or Alcohol Problem in the Past Year among Persons Aged 12 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.35 Perceived Need for Illicit Drug or Alcohol Treatment and Whether Made an Effort to Get Treatment in the Past Year among Persons Aged 12 or Older Classified as Needing But Not Receiving Treatment for an Illicit Drug or Alcohol Problem, by Demographic Characteristics: Numbers in Thousands, 2007 and 2008

G.36 Perceived Need for Illicit Drug or Alcohol Treatment and Whether Made an Effort to Get Treatment in the Past Year among Persons Aged 12 or Older Classified as Needing But Not Receiving Treatment for an Illicit Drug or Alcohol Problem, by Demographic Characteristics: Percentages, 2007 and 2008

G.37 Serious Mental Illness in the Past Year among Persons Aged 18 or Older, by Age Group and Demographic Characteristics: Percentages, 2008

G.38 Received Mental Health Treatment/Counseling in the Past Year among Persons Aged 18 or Older, by Past Year Serious Mental Illness and Demographic Characteristics: Percentages, 2008

G.39 Specific Types of Mental Health Treatment/Counseling Received in the Past Year among Persons Aged 18 or Older, by Demographic Characteristics: Percentages, 2007 and 2008

G.40 Had at Least One Major Depressive Episode (MDE) or MDE with Severe Impairment in the Past Year among Persons Aged 18 or Older, and Receipt of Treatment for Depression in the Past Year among Persons Aged 18 or Older with MDE or MDE with Severe Impairment in the Past Year, by Demographic Characteristics: Percentages, 2008

G.41 Had at Least One Major Depressive Episode (MDE) in the Past Year among Persons Aged 12 to 17, by Demographic Characteristics: Percentages, 2004-2008

G.42 Source of Mental Health Service in the Past Year among Persons Aged 12 to 17: Percentages, 2002-2008

Revised Adult Mental Illness Estimates for 2008 to 2011

The Substance Abuse and Mental Health Services Administration (SAMHSA) has been publishing National Survey on Drug Use and Health (NSDUH) estimates of the prevalence of past year serious mental illness (SMI) and any mental illness (AMI) among adults aged 18 or older since the release of the 2008 NSDUH national findings report. Estimates were based on a model developed in 2008. In 2013, SAMHSA developed a more accurate model for the 2012 data. This revised model incorporates the NSDUH respondent's age and indicators of past year suicide thoughts and depression, along with the variables that were specified in the 2008 model (Kessler-6 [K6] questions on psychological distress and an abbreviated set of questions on impairment in carrying out activities from the World Health Organization Disability Assessment Schedule [WHODAS]), leading to more accurate estimates of SMI and AMI. Estimates, estimation procedures, and definitions described in this report for those measures are based on the 2008 model and not the 2012 revised model. However, the NSDUH detailed tables for 2008 and the mental health detailed tables for 2009 to 2011 at http://samhsa.gov/data/default.aspx have been updated to include estimates of SMI and AMI for adults based on this revised model. Other mental health measures in this report, such as major depressive episode (MDE), serious psychological distress (SPD), and serious thoughts of suicide, were not affected. For further information on the revised model, see the NSDUH short report titled Revised Estimates of Mental Illness from the National Survey on Drug Use and Health at http://samhsa.gov/data/default.aspx.

Highlights

This report presents the first information from the 2008 National Survey on Drug Use and Health (NSDUH), an annual survey sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA). The survey is the primary source of information on the use of illicit drugs, alcohol, and tobacco in the civilian, noninstitutionalized population of the United States aged 12 years old or older. The survey interviews approximately 67,500 persons each year. Unless otherwise noted, all comparisons in this report described using terms such as "increased," "decreased," or "more than" are statistically significant at the .05 level.

Illicit Drug Use

Alcohol Use

Tobacco Use

Initiation of Substance Use (Incidence, or First-Time Use) within the Past 12 Months

Youth Prevention-Related Measures

Substance Dependence, Abuse, and Treatment

Mental Health

1. Introduction

This report presents a first look at results from the 2008 National Survey on Drug Use and Health (NSDUH), an annual survey of the civilian, noninstitutionalized population of the United States aged 12 years old or older. The report presents national estimates of rates of use, numbers of users, and other measures related to illicit drugs, alcohol, and tobacco products. Measures related to mental health problems also are presented, including data on serious mental illness, depression, and the co-occurrence of substance use and mental health problems. The report focuses on trends between 2007 and 2008 and from 2002 to 2008, as well as differences across population subgroups in 2008. Estimates from NSDUH for States and areas within States will be presented in separate reports.

1.1. Summary of NSDUH

NSDUH is the primary source of statistical information on the use of illegal drugs by the U.S. population. Conducted by the Federal Government since 1971, the survey collects data by administering questionnaires to a representative sample of the population through face-to-face interviews at the respondent's place of residence. The survey is sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA), U.S. Department of Health and Human Services, and is planned and managed by SAMHSA's Office of Applied Studies (OAS). Data collection and analysis are conducted under contract with RTI International, Research Triangle Park, North Carolina.1 This section briefly describes the survey methodology; a more complete description is provided in Appendix A.

NSDUH collects information from residents of households and noninstitutional group quarters (e.g., shelters, rooming houses, dormitories) and from civilians living on military bases. The survey excludes homeless persons who do not use shelters, military personnel on active duty, and residents of institutional group quarters, such as jails and hospitals. Appendix D describes surveys that cover populations outside the NSDUH target population.

From 1971 through 1998, the survey employed paper and pencil data collection. Since 1999, the NSDUH interview has been carried out using computer-assisted interviewing (CAI). Most of the questions are administered with audio computer-assisted self-interviewing (ACASI). ACASI is designed to provide the respondent with a highly private and confidential mode for responding to questions in order to increase the level of honest reporting of illicit drug use and other sensitive behaviors. Less sensitive items are administered by interviewers using computer-assisted personal interviewing (CAPI).

The 2008 NSDUH employed a State-based design with an independent, multistage area probability sample within each State and the District of Columbia. The eight States with the largest population (which together account for about half of the total U.S. population aged 12 or older) were designated as large sample States (California, Florida, Illinois, Michigan, New York, Ohio, Pennsylvania, and Texas) and had a sample size of about 3,600 each. For the remaining 42 States and the District of Columbia, the sample size was about 900 per State. The design oversampled youths and young adults, so that each State's sample was approximately equally distributed among three age groups: 12 to 17 years, 18 to 25 years, and 26 years or older.

Nationally, screening was completed at 142,938 addresses, and 68,736 completed interviews were obtained. The survey was conducted from January through December 2008. Weighted response rates for household screening and for interviewing were 89.0 and 74.4 percent, respectively. See Appendix B for more information on NSDUH response rates.

1.2. Limitations on Trend Measurement

Because of the shift in interviewing method in 1999, the estimates from the pre-1999 surveys are not comparable with estimates from the current CAI-based surveys. Although the design of the 2002 through 2008 NSDUHs is similar to the design of the 1999 through 2001 surveys, there are also important methodological differences that affect the comparability of the 2002 to 2008 estimates with estimates from prior surveys. The most important change was the incentive payment started in 2002 and continuing in subsequent surveys. Each NSDUH respondent completing the interview is given $30. Also, the name of the survey was changed in 2002, from the National Household Survey on Drug Abuse (NHSDA) to the current name. Improved data collection quality control procedures were introduced in the survey starting in 2001, and updated population data from the 2000 decennial census were incorporated into the sample weights starting with the 2002 estimates. Analyses of the effects of these factors on NSDUH estimates have shown that 2002 and later data should not be compared with 2001 and earlier data from the survey series to assess changes over time. Appendix C of the 2004 NSDUH report on national findings discusses this in more detail (see OAS, 2005).

Because of changes in the questionnaire, estimates for methamphetamine, stimulants, and psychotherapeutics in this report should not be compared with corresponding estimates in OAS reports for data years prior to 2007. Estimates for 2002 to 2006 for these drug categories in this report, as well as in the 2007 report, incorporate statistical adjustments to enable year-to-year comparisons to be made over the period from 2002 to 2008.

The next section describes questionnaire changes that affect trend measurement for serious psychological distress and major depressive episode.

1.3. New Data on Mental Health

Several important changes were made to the adult mental health section in the 2008 NSDUH questionnaire. These changes provide valuable new data on mental health, but they also affect some of the measures that have been collected in NSDUH since 2004. A brief summary of the changes and their impact is provided below.

From 2004 to 2007, NSDUH collected data for adults aged 18 or older on lifetime and past year major depressive episode (MDE). The survey also included the K6 distress scale with a past 12 month time frame. SAMHSA used the K6 data to generate estimates of serious psychological distress (SPD) in the past 12 months. To address SAMHSA's need for estimates of serious mental illness (SMI), as well as data on suicidal ideation and behavior, OAS modified the NSDUH adult mental health module in 2008 to obtain these data. Scales were added that assessed impairment caused by mental problems. OAS also expanded the K6 questions to ask about the past 30 days (the time frame for which the K6 was originally designed). A Mental Health Surveillance Study (MHSS) was initiated in which a subsample of adults (about 1,500 in 2008) who had completed the NSDUH interview was administered a standard clinical interview by mental health clinicians via paper and pencil over the telephone to determine their SMI status. Using both clinical interview and computer-assisted interview data for the respondents who completed the clinical interview, statistical models were developed that then were applied to the full NSDUH adult sample to produce SMI estimates. See Section B.4.6 in Appendix B for a more complete discussion.

The first estimates from the expanded mental health module, including those for SMI, 30-day SPD, and suicidal thoughts and behavior, are included in Chapter 8 of this report. However, the questionnaire changes caused discontinuities in trends for MDE and 12-month SPD. Analyses of these data have determined that the 2008 data for MDE and 12-month SPD are not comparable with 2007 and earlier data (see Section B.4.4 in Appendix B). Thus, no 12-month SPD data are discussed in the report, and MDE data are presented only for 2008.

No questionnaire changes were made in 2008 that affected MDE items for youths aged 12 to 17 or for the youth and adult mental health service utilization questions. The discussion of estimates for these measures in this report includes comparisons with prior years' data.

1.4. Format of Report and Explanation of Tables

This report has separate chapters that discuss the national findings on seven topics: use of illicit drugs; use of alcohol; use of tobacco products; initiation of substance use; prevention-related issues; substance dependence, abuse, and treatment; and mental health problems and treatment. A final chapter summarizes the results and discusses key findings in relation to other research and survey results. Technical appendices describe the survey (Appendix A), provide technical details on the statistical methods and measurement (Appendix B), offer key NSDUH definitions (Appendix C), discuss other sources of related data (Appendix D), list the references cited in the report (Appendix E), and present selected tabulations of estimates (Appendices F and G). A list of contributors to the production of this report also is provided (Appendix H).

Tables, text, and figures present prevalence measures for the population in terms of both the number of persons and the percentage of the population. Substance use tables show prevalence estimates by lifetime (i.e., ever used), past year, and past month use. Analyses focus primarily on past month use, which also is referred to as "current use." Tables and figures in which estimates are presented by year have footnotes indicating whether the 2008 estimates are significantly different from 2007 or earlier estimates. In some tables and figures, estimates are presented based on data combined from two or more survey years to increase precision of the estimates; those estimates are annual averages based on multiple years of data.

Statistical tests have been conducted for all statements appearing in the text of the report that compare estimates between years or subgroups of the population. Unless explicitly stated that a difference is not statistically significant, all statements that describe differences are significant at the .05 level. Statistically significant differences are described using terms such as "higher," "lower," "increased," and "decreased." Statements that use terms such as "similar," "no difference," "same," or "remained steady" to describe the relationship between estimates denote that a difference is not statistically significant. In addition, a set of estimates for survey years or population subgroups may be presented without a statement of comparison, in which case a statistically significant difference between these estimates is not implied and testing was not conducted.

All estimates presented in the report have met the criteria for statistical reliability (see Section B.2.2 in Appendix B). Estimates that do not meet these criteria are suppressed and do not appear in tables, figures, or text. Subgroups with suppressed estimates are not included in statistical tests of comparisons. For example, a statement that "whites had the highest prevalence" means that the rate among whites was higher than the rate among all nonsuppressed racial/ethnic subgroups, but not necessarily higher than the rate among a subgroup for which the estimate was suppressed.

Data are presented for racial/ethnic groups based on current guidelines for collecting and reporting race and ethnicity data (Office of Management and Budget [OMB], 1997). Because respondents were allowed to choose more than one racial group, a "two or more races" category is presented that includes persons who reported more than one category among the basic groups listed in the survey question (white, black or African American, American Indian or Alaska Native, Native Hawaiian, Other Pacific Islander, Asian, Other). Respondents choosing both Native Hawaiian and Other Pacific Islander but no other categories mentioned above are classified in the combined "Native Hawaiian or Other Pacific Islander" category instead of the "two or more race" category. It should be noted that, except for the "Hispanic or Latino" group, the racial/ethnic groups discussed in this report include only non-Hispanics. The category "Hispanic or Latino" includes Hispanics of any race.

Data also are presented for four U.S. geographic regions and nine geographic divisions within these regions. These regions and divisions, defined by the U.S. Census Bureau, consist of the following groups of States:

Northeast Region - New England Division: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont; Middle Atlantic Division: New Jersey, New York, Pennsylvania.

Midwest Region - East North Central Division: Illinois, Indiana, Michigan, Ohio, Wisconsin; West North Central Division: Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota.

South Region - South Atlantic Division: Delaware, District of Columbia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, West Virginia; East South Central Division: Alabama, Kentucky, Mississippi, Tennessee; West South Central Division: Arkansas, Louisiana, Oklahoma, Texas.

West Region - Mountain Division: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming; Pacific Division: Alaska, California, Hawaii, Oregon, Washington.

Geographic comparisons also are made based on county type, a variable that reflects different levels of urbanicity and metropolitan area inclusion of counties, based on metropolitan area definitions issued by the OMB in June 2003 (OMB, 2003). For this purpose, counties are grouped based on the 2003 rural-urban continuum codes. These codes were originally developed by the U.S. Department of Agriculture (Butler & Beale, 1994). Each county is either inside or outside a metropolitan statistical area (MSA), as defined by the OMB.

Large metropolitan areas have a population of 1 million or more. Small metropolitan areas have a population of fewer than 1 million. Small metropolitan areas are further classified based on whether they have a population of 250,000 or more. Nonmetropolitan areas are outside of MSAs. Counties in nonmetropolitan areas are further classified based on the number of people in the county who live in an urbanized area, as defined by the Census Bureau at the subcounty level. "Urbanized" counties have a population of 20,000 or more in urbanized areas, "less urbanized" counties have at least 2,500 but fewer than 20,000 population in urbanized areas, and "completely rural" counties have populations of fewer than 2,500 in urbanized areas.

1.5. Other NSDUH Reports and Data

Other reports focusing on specific topics of interest will be produced using the 2008 NSDUH data and made available on SAMHSA's website. A report on State-level estimates for 2007-2008 will be available in early 2010.

A comprehensive set of tables, referred to as "detailed tables," is available through the Internet at http://oas.samhsa.gov. The tables are organized into sections based primarily on the topic. Most tables are provided in several parts, showing population estimates (e.g., numbers of drug users), rates (e.g., percentages of population using drugs), and standard errors of all nonsuppressed estimates. A small subset of these detailed tables has been selected for inclusion in Appendices F and G of this report. The appendix tables can be mapped back to the detailed tables by using the table number in parentheses in the upper left corner of each table (e.g., Table G.1 in Appendix G is Table 8.1A in the detailed tables). Additional methodological information on NSDUH, including the questionnaire, is available electronically at the same web address.

Brief descriptive reports and in-depth analytic reports focusing on specific issues or population groups also are produced by OAS. A complete listing of previously published reports from NSDUH and other data sources is available from OAS. Most of these reports also are available through the Internet (http://oas.samhsa.gov). In addition, OAS makes public use data files available to researchers through the Substance Abuse and Mental Health Data Archive (SAMHDA, 2009) at http://www.datafiles.samhsa.gov. Currently, files are available from the 1979 to 2007 surveys.2 The 2008 NSDUH public use file will be available by the end of 2009.

2. Illicit Drug Use

The National Survey on Drug Use and Health (NSDUH) obtains information on nine categories of illicit drug use: use of marijuana, cocaine, heroin, hallucinogens, and inhalants; and the nonmedical use of prescription-type pain relievers, tranquilizers, stimulants, and sedatives. In these categories, hashish is included with marijuana, and crack is considered a form of cocaine. Several drugs are grouped under the hallucinogens category, including LSD, PCP, peyote, mescaline, psilocybin mushrooms, and "Ecstasy" (MDMA). Inhalants include a variety of substances, such as nitrous oxide, amyl nitrite, cleaning fluids, gasoline, spray paint, other aerosol sprays, and glue. The four categories of prescription-type drugs (pain relievers, tranquilizers, stimulants, and sedatives) cover numerous medications available by prescription. They also include drugs within these groupings that originally were prescription medications but currently may be manufactured and distributed illegally, such as methamphetamine, which is included under stimulants. Respondents are asked to report only "nonmedical" use of these drugs, defined as use without a prescription of the individual's own or simply for the experience or feeling the drugs caused. Use of over-the-counter drugs and legitimate use of prescription drugs are not included. NSDUH reports combine the four prescription-type drug groups into a category referred to as "psychotherapeutics."

Estimates of "illicit drug use" reported from NSDUH reflect the use of any of the nine drug categories listed above. Use of alcohol and tobacco products, while illegal for youths, is not included in these estimates, but is discussed in Chapters 3 and 4.

This chapter includes estimates of the nonmedical use of prescription psychotherapeutic drugs and prescription stimulants that take into account data on methamphetamine use based on information obtained from survey items added to NSDUH beginning in 2005. Estimates for these drugs for earlier years when these items were not collected have been adjusted to be comparable with the current estimates. For further information, see Section B.4.6 of the 2007 NSDUH national findings report (Office of Applied Studies [OAS], 2008). The estimates for the nonmedical use of stimulants and psychotherapeutic drugs in this report are not comparable with corresponding estimates in NSDUH reports prior to the 2007 data year, and the methamphetamine use estimates in this report also are not comparable with those in NSDUH reports for survey years prior to 2006.

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Figure 2.1 Past Month Illicit Drug Use among Persons Aged 12 or Older: 2008

Figure 2.1

1 Illicit Drugs include marijuana/hashish, cocaine (including crack), heroin, hallucinogens, inhalants, or prescription-type psychotherapeutics used nonmedically.

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Figure 2.2 Past Month Use of Selected Illicit Drugs among Persons Aged 12 or Older: 2002-2008

Figure 2.2

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 2.3 Past Month Nonmedical Use of Types of Psychotherapeutic Drugs among Persons Aged 12 or Older: 2002-2008

Figure 2.3

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Age

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Figure 2.4 Past Month Illicit Drug Use among Persons Aged 12 or Older, by Age: 2008

Figure 2.4

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Figure 2.5 Past Month Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

Figure 2.5

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Youths Aged 12 to 17

Young Adults Aged 18 to 25

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Figure 2.6 Past Month Use of Selected Illicit Drugs among Young Adults Aged 18 to 25: 2002-2008

Figure 2.6

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Adults Aged 26 or Older

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Figure 2.7 Past Month Illicit Drug Use among Adults Aged 50 to 59: 2002-2008

Figure 2.7

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Gender

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Figure 2.8 Past Month Marijuana Use among Youths Aged 12 to 17, by Gender: 2002-2008

Figure 2.8

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Pregnant Women

Race/Ethnicity

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Figure 2.9 Past Month Illicit Drug Use among Persons Aged 12 or Older, by Race/Ethnicity: 2008

Figure 2.9

Education

College Students

Employment

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Figure 2.10 Past Month Illicit Drug Use among Persons Aged 18 or Older, by Employment Status: 2007 and 2008

Figure 2.10

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.
1 The Other Employment category includes retired persons, disabled persons, homemakers, students, or other persons not in the labor force.

Geographic Area

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Figure 2.11 Past Month Illicit Drug Use among Persons Aged 12 or Older, by County Type: 2008

Figure 2.11

Criminal Justice Populations

Frequency of Use

Association with Cigarette and Alcohol Use

Driving Under the Influence of Illicit Drugs

Source of Prescription Drugs

3. Alcohol Use

The National Survey on Drug Use and Health (NSDUH) includes questions about the recency and frequency of consumption of alcoholic beverages, such as beer, wine, whiskey, brandy, and mixed drinks. An extensive list of examples of the kinds of beverages covered is given to respondents prior to the question administration. A "drink" is defined as a can or bottle of beer, a glass of wine or a wine cooler, a shot of liquor, or a mixed drink with liquor in it. Times when the respondent only had a sip or two from a drink are not considered to be consumption. For this report, estimates for the prevalence of alcohol use are reported primarily at three levels defined for both males and females and for all ages as follows:

Current (past month) use - At least one drink in the past 30 days.

Binge use - Five or more drinks on the same occasion (i.e., at the same time or within a couple of hours of each other) on at least 1 day in the past 30 days.

Heavy use - Five or more drinks on the same occasion on each of 5 or more days in the past 30 days.

These levels are not mutually exclusive categories of use; heavy use is included in estimates of binge and current use, and binge use is included in estimates of current use.

This chapter is divided into two main sections. Section 3.1 describes trends and patterns of alcohol use among the population aged 12 or older. Section 3.2 is particularly concerned with the use of alcohol by persons aged 12 to 20. These persons are under the legal drinking age in all 50 States and the District of Columbia.

3.1. Alcohol Use among Persons Aged 12 or Older

Age

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Figure 3.1 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 or Older, by Age: 2008

Figure 3.1

Gender

Pregnant Women

Race/Ethnicity

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Figure 3.2 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 or Older, by Race/Ethnicity: 2008

Figure 3.2

Note: Due to low precision, estimates for Native Hawaiians or Other Pacific Islanders are not shown.

Education

College Students

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Figure 3.3 Heavy Alcohol Use among Adults Aged 18 to 22, by College Enrollment: 2002-2008

Figure 3.3

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Employment

Geographic Area

Association with Illicit Drug and Tobacco Use

Driving Under the Influence of Alcohol

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Figure 3.4 Driving Under the Influence of Alcohol in the Past Year among Persons Aged 12 or Older: 2002-2008

Figure 3.4

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 3.5 Driving Under the Influence of Alcohol in the Past Year among Persons Aged 16 or Older, by Age: 2008

Figure 3.5

3.2. Underage Alcohol Use

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Figure 3.6 Current Alcohol Use among Persons Aged 12 to 20, by Age: 2002-2008

Figure 3.6

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 3.7 Current, Binge, and Heavy Alcohol Use among Persons Aged 12 to 20, by Gender: 2008

Figure 3.7

4. Tobacco Use

The National Survey on Drug Use and Health (NSDUH) includes a series of questions about the use of tobacco products, including cigarettes, chewing tobacco, snuff, cigars, and pipe tobacco. Cigarette use is defined as smoking "part or all of a cigarette." For analytic purposes, data for chewing tobacco and snuff are combined as "smokeless tobacco."

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Figure 4.1 Past Month Tobacco Use among Persons Aged 12 or Older: 2002-2008

Figure 4.1

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Age

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Figure 4.2 Past Month Tobacco Use among Youths Aged 12 to 17: 2002-2008

Figure 4.2

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 4.3 Past Month Cigarette Use among Persons Aged 12 or Older, by Age: 2008

Figure 4.3

Gender

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Figure 4.4 Past Month Cigarette Use among Youths Aged 12 to 17, by Gender: 2002-2008

Figure 4.4

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Pregnant Women

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Figure 4.5 Past Month Cigarette Use among Women Aged 15 to 44, by Pregnancy Status: Combined Years 2002-2003 to 2007-2008

Figure 4.5

+ Difference between this estimate and the 2007-2008 estimate is statistically significant at the .05 level.

Race/Ethnicity

Education

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Figure 4.6 Past Month Tobacco Use among Adults Aged 18 or Older, by Education: 2008

Figure 4.6

College Students

Employment

Geographic Area

Association with Illicit Drug and Alcohol Use

Frequency of Cigarette Use

5. Initiation of Substance Use

Information on substance use initiation, also known as incidence or first-time use, is important for policymakers and researchers. Measures of initiation are often leading indicators of emerging patterns of substance use. They provide valuable information that can be used to assess the effectiveness of current prevention programs and to focus prevention efforts.

With its large sample size and oversampling of youths aged 12 to 17 and young adults aged 18 to 25, the National Survey on Drug Use and Health (NSDUH) provides a variety of estimates related to substance use (illicit drugs, cigarettes, and alcohol) initiation based on reported age and on year and month at first use. This chapter presents estimates of initiation occurring in the 12 months prior to the interview date. Individuals who initiated use within the past 12 months are referred to as recent or past year initiates. One caveat of this approach is that because the survey interviews persons aged 12 or older and asks about the past 12 months, the initiation estimates will represent some, but not all, of the initiation at age 11 and no initiation occurring at age 10 or younger. This underestimation problem primarily affects estimates of initiation for cigarettes, alcohol, and inhalants because they tend to be initiated at a younger age than other substances. See Section B.4.1 in Appendix B for further discussion of the methods and bias in initiation estimates.

This chapter includes estimates of the number and rate of past year initiation of illicit drug, cigarette, and alcohol use among the total population aged 12 or older and by age and gender categories from the 2002 to 2008 NSDUHs. Also included are initiation estimates that pertain to persons at risk for initiation (i.e., those who had never used as of 12 months prior to the interview date). Some analyses are based on the ages at the time of interview, and others focus on the age at the time of first substance use. Readers need to be aware of these alternative estimation approaches when interpreting NSDUH incidence estimates and pay close attention to the approach used in each situation. Titles and notes on figures and associated detailed tables document which method applies.

For trend measurement, initiation estimates for each year (2002 to 2008) are produced independently based on the data from the survey conducted that year. It should be mentioned that trend estimates of incidence based on long recall periods have not been considered because of concerns about their validity (Gfroerer, Hughes, Chromy, Heller, & Packer, 2004).

Regarding the age at first use estimates, means, as measures of central tendency, are heavily influenced by the presence of extreme values in the data. Thus, for the purposes of this report and unless specified otherwise, the mean age at initiation pertains to persons aged 12 to 49. This constraint was implemented so that the mean age estimates reported would not be influenced by those few respondents who were past year initiates at age 50 or older. Note that this constraint only affects estimates of mean age at initiation; other estimates in this chapter, including the number and prevalence of past year initiates, are among all persons aged 12 or older.

Another important consideration in examining incidence estimates across different drug categories is that substance users typically initiate use of different substances at different times in their lives. Thus, the estimates for past year initiation of specific illicit drugs cannot be added to obtain the overall number of illicit drug initiates because some of the initiates previously had used other drugs. The overall illicit drug initiation estimate only includes the past year initiation of specific drug use that was not preceded by use of other drugs. For example, a respondent who reported initiating marijuana use in the past 12 months is counted as a marijuana initiate. The same respondent also can be counted as an overall illicit drug initiate only if his or her marijuana use initiation was not preceded by use of any other drug (cocaine, heroin, hallucinogens, inhalants, pain relievers, tranquilizers, stimulants, or sedatives). To say it differently, the overall illicit drug initiation estimate only takes into account the first drug initiated. To help clarify this aspect of the incidence data, additional analyses have been generated to identify which specific illicit drug was used at the time of first use of any illicit drug. Furthermore, the overall illicit drug use initiation estimates in this chapter are based on data only from the core section of the questionnaire and do not take account of data from new items on the initiation of methamphetamine use that were added to the noncore section beginning in 2007. See Section B.4.8 in Appendix B of this report for details.

Initiation of Illicit Drug Use

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Figure 5.1 Specific Drug Used When Initiating Illicit Drug Use among Past Year Initiates of Illicit Drugs Aged 12 or Older: 2008

Figure 5.1

Note: The percentages do not add to 100 percent due to rounding or because a small number of respondents initiated multiple drugs on the same day.

Comparison, by Drug

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Figure 5.2 Past Year Initiates for Specific Illicit Drugs among Persons Aged 12 or Older: 2008

Figure 5.2

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Figure 5.3 Mean Age at First Use for Specific Illicit Drugs among Past Year Initiates Aged 12 to 49: 2008

Figure 5.3

Marijuana

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Figure 5.4 Past Year Marijuana Initiates among Persons Aged 12 or Older and Mean Age at First Use of Marijuana among Past Year Marijuana Initiates Aged 12 to 49: 2002-2008

Figure 5.4

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.
1 Mean-age-at-first-use estimates are for recent initiates aged 12 to 49.

Cocaine

Heroin

Hallucinogens

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Figure 5.5 Past Year Hallucinogen Initiates among Persons Aged 12 or Older: 2002-2008

Figure 5.5

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Inhalants

Psychotherapeutics

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Figure 5.6 Past Year Methamphetamine Initiates among Persons Aged 12 or Older and Mean Age at First Use of Methamphetamine among Past Year Methamphetamine Initiates Aged 12 to 49: 2002-2008

Figure 5.6

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.
1 Mean-age-at-first-use estimates are for recent initiates aged 12 to 49.

Alcohol

Tobacco

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Figure 5.7 Past Year Cigarette Initiates among Persons Aged 12 or Older, by Age at First Use: 2002-2008

Figure 5.7

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 5.8 Past Year Cigarette Initiation among Youths Aged 12 to 17 Who Had Never Smoked Prior to the Past Year, by Gender: 2002-2008

Figure 5.8

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

6. Youth Prevention-Related Measures

The National Survey on Drug Use and Health (NSDUH) includes questions for youths aged 12 to 17 about a number of risk and protective factors that may affect the likelihood that they will engage in substance use. Risk factors are individual characteristics and environmental influences associated with an increased vulnerability to the initiation, continuation, or escalation of substance use. Protective factors include individual resilience and other circumstances that are associated with a reduction in the likelihood of substance use. Risk and protective factors include variables that operate at different stages of development and reflect different domains of influence, including the individual, family, peer, school, community, and societal levels (Hawkins, Catalano, & Miller, 1992; Robertson, David, & Rao, 2003). Interventions to prevent substance use generally are designed to ameliorate the influence of risk factors and enhance the effectiveness of protective factors.

This chapter presents findings for youth prevention-related measures collected in the 2008 NSDUH and compares these with findings from previous years. Included are measures of perceived risk from substance use (cigarettes, alcohol, and illicit drugs), perceived availability of substances, being approached by someone selling drugs, perceived parental disapproval of youth substance use, feelings about peer substance use, involvement in fighting and delinquent behavior, participation in religious and other activities, exposure to substance use prevention messages and programs, and parental involvement.

In this chapter, rates of substance use are compared for persons responding differently to questions reflecting risk or protective factors, such as the perceived risk of harm from using a substance. Because the NSDUH data for an individual are collected at only one point in time, it is not possible to determine causal connections from these data. However, a number of research studies of youths have shown that reducing risk factors and increasing protective factors can reduce rates of substance use (Botvin, Botvin, & Ruchlin, 1998). This report shows that marijuana, cigarette, and alcohol use among youths aged 12 to 17 decreased between 2002 and 2008, yet corresponding changes in individual risk and protective factors for the same period may or may not have occurred. There can be many reasons for this, such as the lack of or a weak causal connection, a lagged relationship between the occurrence of a risk factor and the change in drug use behavior, or that individual use is typically the result of multiple simultaneous risk factors rather than a single factor (Newcomb, Maddahian, & Bentler, 1986).

Perceptions of Risk

One factor that can influence whether youths will use tobacco, alcohol, or illicit drugs is the extent to which youths believe these substances might cause them harm. NSDUH respondents were asked how much they thought people risk harming themselves physically and in other ways when they use various substances in certain amounts or frequencies. Response choices for these items were "great risk," "moderate risk," "slight risk," or "no risk."

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Figure 6.1 Past Month Binge Drinking and Marijuana Use among Youths Aged 12 to 17, by Perceptions of Risk: 2008

Figure 6.1

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Figure 6.2 Perceived Great Risk of Cigarette and Alcohol Use among Youths Aged 12 to 17: 2002-2008

Figure 6.2

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 6.3 Perceived Great Risk of Marijuana Use among Youths Aged 12 to 17: 2002-2008

Figure 6.3

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 6.4 Perceived Great Risk of Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

Figure 6.4

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Perceived Availability

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Figure 6.5 Perceived Availability of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2008

Figure 6.5

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 6.6 Approached in the Past Month by Someone Selling Drugs among Youths Aged 12 to 17: 2002-2008

Figure 6.6

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Perceived Parental Disapproval of Substance Use

Feelings about Peer Substance Use

Fighting and Delinquent Behavior

Religious Beliefs and Participation in Activities

Exposure to Substance Use Prevention Messages and Programs

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Figure 6.7 Exposure to Substance Use Prevention Messages and Programs among Youths Aged 12 to 17: 2002-2008

Figure 6.7

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.
1 Estimates are from youths aged 12 to 17 who were enrolled in school in the past year.

Parental Involvement

7. Substance Dependence, Abuse, and Treatment

The National Survey on Drug Use and Health (NSDUH) includes a series of questions to assess the prevalence of substance use disorders (i.e., dependence on or abuse of a substance) in the past 12 months. Substances include alcohol and illicit drugs, such as marijuana, cocaine, heroin, hallucinogens, inhalants, and the nonmedical use of prescription-type psychotherapeutic drugs. These questions are used to classify persons as dependent on or abusing specific substances based on criteria specified in the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) (American Psychiatric Association [APA], 1994).

The questions related to dependence ask about health and emotional problems associated with substance use, unsuccessful attempts to cut down on use, tolerance, withdrawal, reducing other activities to use substances, spending a lot of time engaging in activities related to substance use, or using the substance in greater quantities or for a longer time than intended. The questions on abuse ask about problems at work, home, and school; problems with family or friends; physical danger; and trouble with the law due to substance use. Dependence is considered to be a more severe substance use problem than abuse because it involves the psychological and physiological effects of tolerance and withdrawal. Although individuals may meet the criteria specified here for both dependence and abuse, persons meeting the criteria for both are classified as having dependence, but not abuse. Persons defined with abuse in this report do not meet the criteria for dependence.

This chapter provides estimates of the prevalence and patterns of substance use disorders occurring in the past year from the 2008 NSDUH and compares these estimates against the results from the 2002 through 2007 surveys. It also provides estimates of the prevalence and patterns of the receipt of treatment in the past year for problems related to substance use. This chapter concludes with a discussion of the need for and the receipt of treatment at specialty facilities for problems associated with substance use.

7.1. Substance Dependence or Abuse

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Figure 7.1 Substance Dependence or Abuse in the Past Year among Persons Aged 12 or Older: 2002-2008

Figure 7.1

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 7.2 Dependence on or Abuse of Specific Illicit Drugs in the Past Year among Persons Aged 12 or Older: 2008

Figure 7.2

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Figure 7.3 Dependence on or Abuse of Illicit Drugs, Marijuana, Cocaine, and Pain Relievers in the Past Year among Persons Aged 12 or Older: 2002-2008

FIgure 7.3

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Age at First Use

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Figure 7.4 Alcohol Dependence or Abuse in the Past Year among Adults Aged 21 or Older, by Age at First Use of Alcohol: 2008

Figure 7.4

Age

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Figure 7.5 Dependence on or Abuse of Alcohol and Illicit Drugs among Youths Aged 12 to 17: 2002-2008

Figure 7.5

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Gender

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Figure 7.6 Substance Dependence or Abuse in the Past Year, by Age and Gender: 2008

Figure 7.6

Race/Ethnicity

Education/Employment

Criminal Justice Populations

Geographic Area

7.2. Past Year Treatment for a Substance Use Problem

Estimates described in this section refer to treatment received for illicit drug or alcohol use, or for medical problems associated with the use of illicit drugs or alcohol. This includes treatment received in the past year at any location, such as a hospital (inpatient), rehabilitation facility (outpatient or inpatient), mental health center, emergency room, private doctor's office, prison or jail, or a self-help group, such as Alcoholics Anonymous or Narcotics Anonymous. Persons could report receiving treatment at more than one location. Note that the definition of treatment in this section is different from the definition of specialty treatment described in Section 7.3. Specialty treatment only includes treatment at a hospital (inpatient), a rehabilitation facility (inpatient or outpatient), or a mental health center.

Individuals who reported receiving substance use treatment but were missing information on whether the treatment was specifically for alcohol use or illicit drug use were not counted in estimates of either illicit drug use treatment or in estimates of alcohol use treatment; however, they were counted in estimates for "drug or alcohol use" treatment.

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Figure 7.7 Locations Where Past Year Substance Use Treatment Was Received among Persons Aged 12 or Older: 2008

Figure 7.7

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Figure 7.8 Substances for Which Most Recent Treatment Was Received in the Past Year among Persons Aged 12 or Older: 2008

Figure 7.8

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Figure 7.9 Received Most Recent Treatment in the Past Year for the Use of Pain Relievers among Persons Aged 12 or Older: 2002-2008

Figure 7.9

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

7.3. Need for and Receipt of Specialty Treatment

This section discusses the need for and receipt of treatment for a substance use problem at a "specialty" treatment facility. Specialty treatment is defined as treatment received at any of the following types of facilities: hospitals (inpatient only), drug or alcohol rehabilitation facilities (inpatient or outpatient), or mental health centers. It does not include treatment at an emergency room, private doctor's office, self-help group, prison or jail, or hospital as an outpatient. An individual is defined as needing treatment for an alcohol or drug use problem if he or she met the DSM-IV (APA, 1994) diagnostic criteria for dependence on or abuse of alcohol or illicit drugs in the past 12 months or if he or she received specialty treatment for alcohol use or illicit drug use in the past 12 months.

In this section, an individual needing treatment for an illicit drug use problem is defined as receiving treatment for his or her drug use problem only if he or she reported receiving specialty treatment for drug use in the past year. Thus, an individual who needed treatment for illicit drug use but only received specialty treatment for alcohol use in the past year or who received treatment for illicit drug use only at a facility not classified as a specialty facility was not counted as receiving treatment for drug use. Similarly, an individual who needed treatment for an alcohol use problem was only counted as receiving alcohol use treatment if the treatment was received for alcohol use at a specialty treatment facility. Individuals who reported receiving specialty substance use treatment but were missing information on whether the treatment was specifically for alcohol use or drug use were not counted in estimates of specialty drug use treatment or in estimates of specialty alcohol use treatment; however, they were counted in estimates for "drug or alcohol use" treatment.

In addition to questions about symptoms of substance use problems that are used to classify respondents' need for treatment based on DSM-IV criteria, NSDUH includes questions asking respondents about their perceived need for treatment (i.e., whether they felt they needed treatment or counseling for illicit drug use or alcohol use). In this report, estimates for perceived need for treatment are only discussed for persons who were classified as needing treatment (based on DSM-IV criteria) but did not receive treatment at a specialty facility. Similarly, estimates for whether a person made an effort to get treatment are only discussed for persons who felt the need for treatment.

Illicit Drug or Alcohol Use Treatment and Treatment Need

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Figure 7.10 Past Year Perceived Need for and Effort Made to Receive Specialty Treatment among Persons Aged 12 or Older Needing But Not Receiving Treatment for Illicit Drug or Alcohol Use: 2008

Figure 7.10

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Figure 7.11 Reasons for Not Receiving Substance Use Treatment among Persons Aged 12 or Older Who Needed and Made an Effort to Get Treatment But Did Not Receive Treatment and Felt They Needed Treatment: 2005-2008 Combined

Figure 7.11

Illicit Drug Use Treatment and Treatment Need

Alcohol Use Treatment and Treatment Need

8. Mental Health

This chapter presents findings on mental health problems in the United States, including the prevalence of serious mental illness (SMI), serious psychological distress (SPD), suicidal thoughts and behavior, and major depressive episode (MDE). The association of these problems with substance use and substance dependence or abuse (i.e., substance use disorder) is discussed. Also reported here are the rates of treatment for depression (among those with MDE) in the past year among adults aged 18 or older and youths aged 12 to 17, the percentages of adults and youths who received mental health care in the past year, and the percentage of adults who had an unmet need for mental health care in the past year.

Serious Mental Illness

Public Law No. 102-321, the Alcohol, Drug Abuse, and Mental Health Administration Reorganization Act of 1992, established a block grant for U.S. States to fund community mental health services for adults with SMI. The law required States to include prevalence estimates in their annual applications for block grant funds. This legislation also required the Substance Abuse and Mental Health Services Administration (SAMHSA) to develop an operational definition of SMI. SAMHSA defined SMI as persons aged 18 or older who currently or at any time in the past year have had diagnosable mental, behavioral, or emotional disorder (excluding developmental and substance use disorders) of sufficient duration to meet diagnostic criteria specified within the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (American Psychiatric Association [APA], 1994) that has resulted in serious functional impairment, which substantially interferes with or limits one or more major life activities.

To establish the means to generate estimates of SMI in the United States, SAMHSA conducted a methodological study—the Mental Health Surveillance Study (MHSS)—to calibrate mental health questionnaire items in the National Survey on Drug Use and Health (NSDUH) with a "gold standard" clinical psychiatric interview and assessment of functioning. A split-sample design was used to administer the 12-month K6 distress scale and either an abbreviated World Health Organization Disability Assessment Schedule (WHODAS) or the Sheehan Disability Scale (SDS) to each respondent aged 18 or older. A subsample of 1,502 adults selected from the main study participated in the calibration study by agreeing to undergo additional mental health assessment via a telephone interview. An analysis was conducted to determine the statistical models (using K6 plus WHODAS items or K6 plus SDS) that accurately predict SMI status as determined by the clinical interview and assessment of function. The analyses found that the WHODAS impairment measure performed slightly better than the SDS, so the WHODAS has been retained as the only impairment scale in the survey instrument for 2009 going forward. A description of the MHSS design and results may be found in Section B.4.6 in Appendix B.

Serious Psychological Distress

As a direct outcome of the MHSS, this report focuses on a past 30 day indicator of SPD rather than a past year reference period as has been reported in previous national findings reports. SPD is defined as having a score of 13 or higher on the 30-day K6 scale. Based on responses about symptoms (on the K6) in the past 30 days, this measure of SPD now more closely corresponds with SPD reference periods reported in other surveys, such as the National Health Interview Survey (NHIS) and the Behavioral Risk Factor Surveillance System (BRFSS). Although the differing modes and contexts of the other surveys prevent direct comparisons of SPD prevalence, there is utility in examining health and behavior correlates of SPD within each survey. Further description of the SPD measure may be found in Section B.4.5 in Appendix B.

Suicidal Thoughts and Behavior

Responding to a need for national data on the prevalence of suicidal thoughts and behavior, a brief module was added to the 2008 NSDUH questionnaire. Suicidality data have been (and continue to be) collected within the context of the MDE module; however, that approach did not capture respondents who screened out of the depression module before they were asked about suicide and did not specifically assess suicidal thoughts and behaviors in the past 12 months. The current module asks all adult respondents if they had serious thoughts of suicide, and if they had thoughts of suicide, whether they made suicide plans or attempts in the past year and further, if an attempt was made, whether the respondent received medical attention or hospitalization as a result of attempted suicide.

Major Depressive Episode (Depression)

A module of questions designed to obtain measures of lifetime and past year prevalence of MDE, the level of functional impairment caused by MDE in the past year, and treatment for depression has been administered to adults aged 18 or older and youths aged 12 to 17 since 2004. Some questions in the adolescent depression module differ slightly from the adult depression module to make them more appropriate for youths. Given these differences, adult and youth depression estimates are presented separately in this chapter.

MDE is defined as a period of at least 2 weeks when a person experienced a depressed mood or loss of interest or pleasure in daily activities and had at least four of seven additional symptoms reflecting the criteria as described in the DSM-IV. It should be noted that unlike the DSM-IV criteria for MDE, no exclusions were made in NSDUH for depressive symptoms caused by medical illness, bereavement, or substance use disorders. Impairment is defined by the level of role interference reported to be caused by MDE in the past 12 months. For adults aged 18 or older, the SDS role domains are (1) home management, (2) work, (3) close relationships with others, and (4) social life. The role domains are assessed on a 0 to 10 scale with impairment categories of "none" (0), "mild" (1-3), "moderate" (4-6), "severe" (7-9), and "very severe" (10). The role domains for youths aged 12 to 17 are slightly modified to be made age appropriate, but are assessed on the same 0 to 10 scale described for adults. The specific questions used to measure MDE and role impairment and the scoring algorithm for these responses are included in Section B.4.7 in Appendix B.

One consequence of the MHSS is that the measures inserted to accommodate it (i.e., the past 30 day K6 scale, the functional impairment scale[s], and the suicidal thoughts and behavior items) are suspected of having some impact on respondents' reporting of symptoms in the adult MDE module. As a result, direct comparison with previous years of data is compromised, requiring that a new MDE trend begin with the 2008 data. To facilitate comparison with the 2009 MDE estimates, only data from the sample of respondents receiving the WHODAS items are presented in this report.

Comparing the Measures

Although the populations classified with SMI, MDE, and SPD substantially overlap, the definitions used for the three measures differ distinctly. Meeting the criteria for SMI indicates that a respondent endorsed having symptoms and related functional impairment at a level that is predictive of having a clinically significant mental disorder and functional impairment as measured by a "gold standard" clinical interview. Meeting the criteria for past year MDE indicates that a respondent had the specific physical and emotional symptom profile indicative of MDE for 2 weeks or more in the past 12 months as described in the DSM-IV. (MDE is known to be a fairly common disorder that often includes significant impairment in a person's functioning at work, at home, and in his or her social life.) Meeting the criteria for past 30 day SPD indicates a respondent recently experienced heightened distress symptomatology that may be affecting health and behavior. This distress may be part of a chronic psychological disturbance (even SMI) or may represent a temporary disturbance (e.g., in reaction to an acute stressor) that could subside after a brief period of adjustment.

Mental Health Service Utilization

This chapter also presents data on mental health care among adults aged 18 or older and youths aged 12 to 17. Initiated in 2000, the mental health service utilization modules are asked of respondents regardless of SMI, MDE, or SPD status. In the adult module, respondents are asked whether they received treatment or counseling for any problem with emotions, "nerves," or mental health in the past year in any inpatient or outpatient setting or used prescription medication for a mental or emotional condition. The treatment questions in this module are generic in that they do not ask specifically about treatment for a particular disorder, as do the questions in the MDE module. Consequently, references to treatment or counseling for any problem with emotions, nerves, or mental health are described broadly as "mental health service use" or receiving/needing "mental health care." Of note, it is possible for a respondent to have indicated receipt of treatment for depression without having indicated that he or she received services for any problems with emotions, nerves, or mental health.

In NSDUH, questions designed to assess mental health service utilization asked of youths differ from those asked of adults. Youths aged 12 to 17 are asked whether they received any treatment or counseling within the 12 months prior to the interview for problems with behavior or emotions in the specialty mental health setting (outpatient or inpatient care), the general medical setting (pediatrician or family physician care for emotional or behavior problems), or the education setting (talked with a counselor, psychologist, or teacher; or received special education services while in a regular classroom; or placed in a special classroom, special program, or special school). Youths also are asked for the number of nights spent in overnight facilities, the number of visits they had to outpatient mental health providers, and the reason(s) for the most recent stay or visit. Both the youth and the adult mental health questions specifically exclude treatment for problems with substance use because substance use treatment is assessed in other interview modules.

Estimates of unmet need for mental health care are reported for adults. Unmet need is established using a question that asks whether a respondent perceived a need for, but did not receive mental health treatment or counseling at any time in the 12 months prior to the NSDUH interview. This measure also includes persons who received some type of mental health service in the past 12 months, but reported a perceived need for additional services they did not receive.

It is important to note that because the survey covers the U.S. civilian, noninstitutionalized population, persons residing in long-term psychiatric or other institutions continuously throughout the year were not included in the NSDUH sampling frame. Persons who were hospitalized or institutionalized for a period of time during 2008, but who resided in households during the rest of the year, were included in the sample.

8.1. Adults Aged 18 or Older

Prevalence of Serious Mental Illness among Adults

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Figure 8.1 Serious Mental Illness in the Past Year among Adults Aged 18 or Older, by Age and Gender: 2008

Figure 8.1

Mental Health Service Use among Adults with Serious Mental Illness

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Figure 8.2 Number of Types of Mental Health Services Received in the Past Year among Persons Aged 18 or Older with Past Year Serious Mental Illness Who Received Mental Health Services in the Past Year: 2008

Figure 8.2

Note: The three types of mental health care are receiving inpatient care, outpatient care, or prescription medication.

Serious Mental Illness and Substance Use and Dependence or Abuse among Adults

Mental Health Care among Adults with Co-Occurring Serious Mental Illness and Substance Use Disorders

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Figure 8.3 Past Year Mental Health Care and Treatment for Substance Use Problems among Adults Aged 18 or Older with Both Serious Mental Illness and a Substance Use Disorder: 2008

Figure 8.3

Note: The percentages add to less than 100 percent because of rounding.
Note: Mental health care is defined as having received inpatient care or outpatient care or having used prescription medication for problems with emotions, nerves, or mental health. Treatment for substance use problems refers to treatment at a hospital (inpatient), rehabilitation facility (inpatient or outpatient), or mental health center in order to reduce or stop drug or alcohol use, or for medical problems associated with drug or alcohol use.

Prevalence of Suicidal Thoughts and Behavior among Adults

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Figure 8.4 Suicidal Thoughts in the Past Year among Adults Aged 18 or Older, by Age and Gender: 2008

Figure 8.4

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Figure 8.5 Suicidal Thoughts and Behavior in the Past Year among Adults Aged 18 or Older: 2008

Figure 8.5

Prevalence of Major Depressive Episode among Adults

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Figure 8.6 Major Depressive Episode in the Past Year among Adults Aged 18 or Older, by Severe Impairment, Age, and Gender: 2008

Figure 8.6

Note: Respondents with an unknown level of impairment were included in the estimates for Major Depressive Episode without Severe Impairment.

Major Depressive Episode and Substance Use and Dependence or Abuse among Adults

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Figure 8.7 Substance Dependence or Abuse among Adults Aged 18 or Older, by Major Depressive Episode in the Past Year: 2008

Figure 8.7

Treatment for Major Depressive Episode among Adults

Prevalence of Past 30 Day Serious Psychological Distress among Adults

Serious Psychological Distress and Substance Use among Adults

Mental Health Service Use and Unmet Need for Mental Health Care among Adults

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Figure 8.8 Past Year Mental Health Service Use among Adults Aged 18 or Older, by Type of Care: 2002-2008

Figure 8.8

+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

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Figure 8.9 Reasons for Not Receiving Mental Health Services in the Past Year among Adults Aged 18 or Older with an Unmet Need for Mental Health Care Who Did Not Receive Mental Health Services: 2008

Figure 8.9

8.2. Youths Aged 12 to 17

Prevalence of Major Depressive Episode among Youths

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Figure 8.10 Major Depressive Episode in the Past Year among Youths Aged 12 to 17, by Severe Impairment, Age, and Gender: 2008

Figure 8.10

Note: Respondents with an unknown level of impairment were included in the estimates for Major Depressive Episode without Severe Impairment.

Major Depressive Episode and Substance Use among Youths

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Figure 8.11 Substance Use among Youths Aged 12 to 17, by Major Depressive Episode in the Past Year: 2008

Figure 8.11

Treatment for Major Depressive Episode among Youths

Mental Health Service Use among Youths

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Figure 8.12 Past Year Mental Health Service Use among Youths Aged 12 to 17, by Gender: 2008

Figure 8.12

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Figure 8.13 Number of Outpatient Visits in the Past Year among Youths Aged 12 to 17 Who Received Outpatient Specialty Mental Health Services: 2008

Figure 8.13

9. Discussion of Trends in Substance Use among Youths and Young Adults

This report presents findings from the 2008 National Survey on Drug Use and Health (NSDUH). Conducted since 1971 and previously named the National Household Survey on Drug Abuse (NHSDA), the survey underwent several methodological improvements in 2002 that have affected prevalence estimates. As a result, the 2002 through 2008 estimates are not comparable with estimates from 2001 and earlier surveys. Therefore, the primary focus of the report is on comparisons of measures of substance use and mental health problems across subgroups of the U.S. population in 2008, changes between 2007 and 2008, and changes between 2002 and 2008. This chapter provides an additional discussion of the findings concerning a topic of great interest—trends in substance use among youths and young adults.

An important step in the analysis and interpretation of NSDUH or any other survey data is to compare the results with those from other data sources. This can be difficult sometimes because the other surveys typically have different purposes, definitions, and designs. Research has established that surveys of substance use and other sensitive topics often produce inconsistent results because of different methods used. Thus, it is important to understand that conflicting results often reflect differing methodologies, not incorrect results. Despite this limitation, comparisons can be very useful. Consistency across surveys can confirm or support conclusions about trends and patterns of use, and inconsistent results can point to areas for further study. Further discussion of this issue is included in Appendix D, along with descriptions of methods and results from other sources of substance use and mental health data.

Unfortunately, few additional data sources are available at this time to compare with NSDUH results. One established source is Monitoring the Future (MTF), a study sponsored by the National Institute on Drug Abuse (NIDA). MTF surveys students in the 8th, 10th, and 12th grades in classrooms during the spring of each year, and it also collects data by mail from a subsample of adults who had participated earlier in the study as 12th graders (Johnston, O'Malley, Bachman, & Schulenberg, 2008a, 2008b, 2009). Historically, NSDUH rates of substance use among youths have been lower than those of MTF, and occasionally the two surveys have shown different trends over a short time period. Nevertheless, the two sources have shown very similar long-term trends in prevalence. NSDUH and MTF rates of substance use generally have been similar among young adults, and the two sources also have shown similar trends.

A comparison of NSDUH and MTF estimates for 2002 to 2008 is shown in Tables 9.1 and 9.2 at the end of this chapter for several substances that are defined similarly in the two surveys. For comparison purposes, MTF data on 8th and 10th graders are combined to give an age range close to 12 to 17 years, the standard youth age group for NSDUH. Appendix D provides comparisons according to MTF definitions (8th, 10th, and 12th grades). MTF follow-up data on persons aged 19 to 24 provide the closest match on age to estimates for NSDUH young adults aged 18 to 25. The NSDUH results are remarkably consistent with MTF trends for both youths and young adults, as discussed below.

Both surveys generally show decreases between 2002 and 2008 in the percentages of youths who used marijuana, cocaine, Ecstasy, LSD, alcohol, and cigarettes in the lifetime, past year, and past month (Table 9.1). Exceptions were for the past month use of LSD in both NSDUH and MTF data and the past month use of Ecstasy in the NSDUH data. The hallucinogen trends are discussed in more detail below. Both surveys show no decrease in the rates of past year and past month inhalant use among youths between 2002 and 2008, and only NSDUH shows a significant decrease in lifetime use. The consistency between NSDUH and MTF trend data is found not only in terms of the specific drugs showing decreases, but also in terms of the magnitude of the decreases. Despite the higher levels of prevalence estimated from MTF, the two surveys show very similar rates of change in past month prevalence, especially for the three substances used most commonly by youths: alcohol, cigarettes, and marijuana. Between 2002 and 2008, the rate of current alcohol use among youths declined 17 percent according to NSDUH and 19 percent according to MTF, and between 2007 and 2008 the declines were 8 and 9 percent, respectively. Current cigarette use prevalence rates in 2008 were 30 percent lower in NSDUH and 32 percent lower in MTF compared with 2002 rates. For past month marijuana use, the NSDUH decline from 2002 to 2008 was 18 percent, and the MTF decline was 25 percent.

In both surveys, the decline in marijuana use among youths between 2002 and 2008 was driven by decreases early in the 7-year period, while in the most recent years, little change has occurred in the rate of use. Between 2006 and 2008, there was no significant change in rates of lifetime, past year, or past month marijuana use for youths in NSDUH (aged 12 to 17) or MTF (8th and 10th graders).

Data on young adults also show similar trends in the two surveys, although not as consistent as for the youth data (Table 9.2). Potential reasons for differences from the data for youths are the relatively smaller MTF sample size for young adults and possible bias in the MTF sample due to noncoverage of school dropouts and a low overall response rate, considering nonresponse by schools, by students in the 12th grade survey, and in the follow-up mail survey.

Both surveys show declines between 2002 and 2008 for past year and past month cigarette and marijuana use among young adults, although the decline in past month marijuana use in NSDUH was not significant. In addition, the extent of the declines in current cigarette and marijuana use for young adults in NSDUH from 2002 through 2008 were less than the corresponding declines for young adults in MTF. Past month marijuana prevalence among young adults declined 5 percent according to NSDUH and by 13 percent according to MTF. Similarly, the prevalence of past month cigarette use among young adults in NSDUH declined by 13 percent over this period and by 23 percent in MTF. Both surveys show no significant change between 2002 and 2008 in the rate of current alcohol use among young adults. A significant decline in past month cocaine use between 2006 and 2008 is seen in the NSDUH data. The MTF data show a similar drop in use between 2006 and 2008 (although not statistically significant).

Both NSDUH and MTF generally show decreases for both youths and young adults in the past year use of Ecstasy and LSD between 2002 and 2004, then a leveling in 2005. The 2006, 2007, and 2008 data from NSDUH show evidence of a possible resurgence in the use of these two hallucinogens among both youths and young adults. Between 2005 and 2008, there were increases in the use of Ecstasy in the lifetime among youths according to NSDUH (from 1.6 to 2.1 percent) and past year (from 1.0 to 1.4 percent); past month use among youths increased from 0.3 to 0.4 percent between 2007 and 2008. LSD use among youths also increased between 2007 and 2008 in the lifetime (0.8 to 1.1 percent) and in the past year (0.5 to 0.7 percent). Past year Ecstasy and LSD estimates among youths in MTF were higher in 2008 than in 2006, but these differences were not statistically significant (Figure 9.1). For young adults in NSDUH, past year Ecstasy use increased from 3.1 percent in 2005 to 3.9 percent in 2008, and LSD use increased from 1.0 to 1.5 percent during that same period. No significant changes were observed in the MTF data on past year Ecstasy use for young adults between 2004 and 2008. However, past year LSD use among young adults in MTF in 2008 was significantly greater than in 2004 and 2005.

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Figure 9.1 Past Year Ecstasy and LSD Use among Youths in NSDUH and MTF: 2002-2008

Figure 9.1

MTF = Monitoring the Future; NSDUH = National Survey on Drug Use and Health.
+ Difference between this estimate and the 2008 estimate is statistically significant at the .05 level.

Data on availability and perceived risk from NSDUH and MTF provide important context for these emerging trends. Both surveys indicate diminishing availability of these drugs in early years of the decade, but a plateau in recent years. In NSDUH, the percentage of youths aged 12 to 17 reporting that LSD is easy to get declined from 19.4 percent in 2002 to 14.0 percent in 2006, but the rate has not changed since then (13.8 percent in 2008). MTF (8th and 10th graders combined) has shown the same trend for perceived availability of LSD (21.0 percent in 2002, 15.0 percent in 2006, and 15.1 percent in 2008). Although NSDUH does not ask about availability of Ecstasy, MTF showed similar trends for perceived availability of Ecstasy (31.9 percent in 2002, 21.0 percent in 2006, and 20.4 percent in 2008). Measures of youths' perceptions of risk in using these hallucinogens declined during the period from 2002 to 2008 in both surveys. Declining perceived risk could lead to more young people initiating use of these drugs and could be contributing to the increase from 2005 to 2008 in the number of past year initiates of Ecstasy (from 615,000 to 894,000) and LSD (from 243,000 to 394,000) among persons aged 12 or older.

Another source of data on trends in the use of drugs among youths is the Youth Risk Behavior Survey (YRBS), sponsored by the Centers for Disease Control and Prevention. YRBS surveys students in the 9th through 12th grades in classrooms every other year during the spring (Eaton et al., 2008). The most recent survey was completed in 2007. YRBS has generally shown higher prevalence rates but similar long-term trends when compared with NSDUH and MTF. However, comparisons between YRBS and NSDUH or MTF are less straightforward because of the different periodicity (i.e., biennially instead of annually) and ages covered, the limited number of drug use questions, and smaller sample size in the YRBS. For the substances for which information on current use is collected in the YRBS, including alcohol, cigarettes, marijuana, and cocaine, the YRBS trend results between 2001 and 2007 are consistent with NSDUH and MTF (Eaton et al., 2008; Grunbaum et al., 2002). YRBS data for the combined grades 9 through 12 showed no significant change in current alcohol use (47.1 percent in 2001 and 44.7 percent in 2007), but decreases in cigarette use (28.5 percent in 2001, 20.0 percent in 2007), marijuana use (23.9 percent in 2001, 19.7 percent in 2007), and cocaine use (4.2 percent in 2001, 3.3 percent in 2007).

Although changes in NSDUH survey methodology preclude direct comparisons of recent estimates with estimates from before 2002, it is important to put the recent trends in context by reviewing longer term trends in use. NSDUH data (prior to the design changes in 1999 and 2002) on youths aged 12 to 17 and MTF data on high school seniors have shown substantial increases in youth illicit drug use during the 1970s, reaching a peak in the late 1970s. Both surveys then showed significant declines throughout the 1980s until about 1992, when rates reached a low point. These trends were driven by the trend in marijuana use. With the start of annual data collection in NSDUH in 1991, along with the biennial YRBS and the annual 8th and 10th grade samples in MTF, trends among youths are well documented since the low point that occurred in the early 1990s. Although they employ different survey designs and cover different age groups, the three surveys are consistent in showing increasing rates of marijuana use during the early to mid-1990s, reaching a peak in the late 1990s, although not as high as in the late 1970s, followed by declines in use after the turn of the 21st century and a leveling in the most recent years (Figure 9.2).

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Figure 9.2 Past Month Marijuana Use among Youths in NSDUH, MTF, and YRBS: 1971-2008

Figure 9.2

MTF = Monitoring the Future; NSDUH = National Survey on Drug Use and Health; YRBS = Youth Risk Behavior Survey.
Note: NSDUH data for youths aged 12 to 17 are not presented for 1999 to 2001 because of design changes in the survey. These design changes preclude direct comparisons of estimates from 2002 to 2008 with estimates prior to 1999.

Table 9.1 – Comparison of NSDUH and MTF Prevalence Estimates among Youths: Percentages, 2002-2008
Substance/
Time Period
NSDUH
(2002)
NSDUH
(2003)
NSDUH
(2004)
NSDUH
(2005)
NSDUH
(2006)
NSDUH
(2007)
NSDUH
(2008)
MTF
(2002)
MTF
(2003)
MTF
(2004)
MTF
(2005)
MTF
(2006)
MTF
(2007)
MTF
(2008)
-- Not available.
NOTE: NSDUH data are for youths aged 12 to 17, and MTF data are simple averages of estimates for 8th and 10th graders. MTF data for 8th and 10th graders are reported in Johnston, O'Malley, Bachman, and Schulenberg (2009a). MTF design effects used for variance estimation are reported in Johnston, O'Malley, Bachman, and Schulenberg (2008b).
a Difference between this estimate and 2008 estimate is statistically significant at the .05 level.
Sources: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, 2004, 2005, 2006, 2007, and 2008. University of Michigan, The Monitoring the Future Study, 2002, 2003, 2004, 2005, 2006, 2007, and 2008.
Marijuana                            
Lifetime 20.6a 19.6a 19.0a 17.4 17.3 16.2 16.5 29.0a 27.0a 25.7a 25.3a 23.8 22.6 22.3
Past Year 15.8a 15.0a 14.5a 13.3 13.2 12.5 13.0 22.5a 20.5a 19.7a 19.4a 18.5 17.5 17.4
Past Month 8.2a 7.9a 7.6a 6.8 6.7 6.7 6.7 13.1a 12.3a 11.2a 10.9a 10.4 10.0 9.8
Cocaine                            
Lifetime 2.7a 2.6a 2.4a 2.3a 2.2a 2.1 1.9 4.9a 4.4 4.4 4.5 4.1 4.2 3.8
Past Year 2.1a 1.8a 1.6a 1.7a 1.6a 1.5a 1.2 3.2a 2.8 2.9 2.9 2.6 2.7 2.4
Past Month 0.6a 0.6a 0.5 0.6a 0.4 0.4 0.4 1.4a 1.1 1.3a 1.3 1.3 1.1 1.0
Ecstasy                            
Lifetime 3.3a 2.4 2.1 1.6a 1.9 1.8a 2.1 5.5a 4.3a 3.6 3.4 3.5 3.8 3.4
Past Year 2.2a 1.3 1.2 1.0a 1.2 1.3 1.4 3.9a 2.6 2.1 2.2 2.1 2.5 2.3
Past Month 0.5 0.4 0.3 0.3 0.3 0.3a 0.4 1.6a 0.9 0.8 0.8 1.0 0.9 1.0
LSD                            
Lifetime 2.7a 1.6a 1.2 1.1 0.9 0.8a 1.1 3.8a 2.8 2.3 2.2 2.2 2.3 2.3
Past Year 1.3a 0.6 0.6 0.6 0.4a 0.5a 0.7 2.1a 1.5 1.4 1.4 1.3 1.5 1.6
Past Month 0.2 0.2 0.2 0.1 0.1 0.1 0.2 0.7 0.6 0.6 0.6 0.6 0.6 0.6
Inhalants                            
Lifetime 10.5a 10.7a 11.0a 10.5a 10.1a 9.6 9.3 14.4 14.3 14.9 15.1 14.7 14.6 14.3
Past Year 4.4 4.5a 4.6a 4.5a 4.4 3.9 3.9 6.8 7.1 7.8 7.8 7.8 7.5 7.4
Past Month 1.2 1.3 1.2 1.2 1.3 1.2 1.1 3.1 3.2 3.5 3.2 3.2 3.2 3.1
Alcohol                            
Lifetime 43.4a 42.9a 42.0a 40.6a 40.4a 39.4 38.3 57.0a 55.8a 54.1a 52.1a 51.0a 50.3a 48.6
Past Year 34.6a 34.3a 33.9a 33.3a 32.9a 31.8 30.8 49.4a 48.3a 47.5a 45.3a 44.7a 44.1a 42.3
Past Month 17.6a 17.7a 17.6a 16.5a 16.6a 15.9a 14.6 27.5a 27.6a 26.9a 25.2a 25.5a 24.7a 22.4
Cigarettes                            
Lifetime 33.3a 31.0a 29.2a 26.7a 25.8a 23.7 22.9 39.4a 35.7a 34.3a 32.4a 30.4a 28.4a 26.1
Past Year 20.3a 19.0a 18.4a 17.3a 17.0a 15.7 15.0 -- -- -- -- -- -- --
Past Month 13.0a 12.2a 11.9a 10.8a 10.4a 9.8a 9.1 14.2a 13.5a 12.6a 12.1a 11.6a 10.6a 9.6
Table 9.2 – Comparison of NSDUH and MTF Prevalence Estimates among Young Adults: Percentages, 2002-2008
Substance/
Time Period
NSDUH
(2002)
NSDUH
(2003)
NSDUH
(2004)
NSDUH
(2005)
NSDUH
(2006)
NSDUH
(2007)
NSDUH
(2008)
MTF
(2002)
MTF
(2003)
MTF
(2004)
MTF
(2005)
MTF
(2006)
MTF
(2007)
MTF
(2008)
-- Not available.
NOTE: NSDUH data shown in this table are for persons aged 18 to 25.
NOTE: MTF data shown in this table are for persons aged 19 to 24. These estimates are simple averages of modal age groups 19-20, 21-22, and 23-24 as reported in Johnston, O'Malley, and Bachman (2003) and in Johnston, O'Malley, Bachman, and Schulenberg (2004, 2005, 2006, 2007, 2008a, 2009b).
NOTE: For the 19 to 24 age group in the MTF data, significance tests were performed assuming independent samples between years an odd number of years apart because two distinct cohorts a year apart were monitored longitudinally at 2-year intervals. Although appropriate for comparisons of 2003, 2005, and 2007 estimates with 2008 estimates, this assumption results in conservative tests for comparisons of 2002, 2004, and 2006 estimates with 2008 estimates because it does not take into account covariances that are associated with repeated observations from the longitudinal samples. Estimates of covariances were not available.
a Difference between this estimate and 2008 estimate is statistically significant at the .05 level.
Sources: SAMHSA, Office of Applied Studies, National Survey on Drug Use and Health, 2002, 2003, 2004, 2005, 2006, 2007, and 2008. University of Michigan, The Monitoring the Future Study, 2002, 2003, 2004, 2005, 2006, 2007, and 2008.
Marijuana                            
Lifetime 53.8a 53.9a 52.8a 52.4a 52.4a 50.8 50.4 56.1a 56.4a 55.6a 54.4 53.8 53.9 53.0
Past Year 29.8a 28.5 27.8 28.0 28.0 27.5 27.6 34.2a 33.0 31.6 31.4 30.9 31.0 30.9
Past Month 17.3 17.0 16.1 16.6 16.3 16.4 16.5 19.8a 19.9a 18.2 17.0 17.0 17.5 17.3
Cocaine                            
Lifetime 15.4a 15.0 15.2 15.1 15.7a 15.0 14.4 12.9 14.5a 14.3a 12.6 13.6 12.4 12.2
Past Year 6.7a 6.6a 6.6a 6.9a 6.9a 6.4a 5.5 6.5 7.3a 7.8a 6.9 7.0 6.3 6.0
Past Month 2.0a 2.2a 2.1a 2.6a 2.2a 1.7 1.5 2.5 2.6 2.4 2.1 2.4 1.9 1.9
Ecstasy                            
Lifetime 15.1a 14.8a 13.8a 13.7a 13.4a 12.8 12.1 16.0a 16.6a 14.9a 12.4a 11.5 9.5 10.1
Past Year 5.8a 3.7 3.1a 3.1a 3.8 3.5 3.9 8.0a 5.3a 3.3 3.4 3.6 2.8 3.8
Past Month 1.1 0.7 0.7 0.8 1.0a 0.7 0.9 1.6 1.0 0.8 0.6 0.9 0.3 0.9
LSD                            
Lifetime 15.9a 14.0a 12.1a 10.5a 8.9a 7.3a 6.5 13.9b 13.8b 10.4b 7.9b 6.7 5.9 5.6
Past Year 1.8 1.1a 1.0a 1.0a 1.2 1.1a 1.5 2.4b 1.5 1.2 1.1 1.5 1.4 1.9
Past Month 0.1a 0.2 0.3 0.2 0.2a 0.2 0.3 0.4 0.2 0.2 0.2 0.3 0.3 0.5
Inhalants                            
Lifetime 15.7a 14.9a 14.0a 13.3a 12.5a 11.3a 10.4 11.7b 11.4b 10.6b 9.3 9.7 7.5 8.4
Past Year 2.2a 2.1a 2.1a 2.1a 1.8 1.6 1.6 2.2b 1.5 2.3b 1.6 1.8 1.1 1.7
Past Month 0.5a 0.4 0.4 0.5 0.4 0.4 0.3 0.8 0.3 0.4 0.3 0.4 0.3 0.6
Alcohol                            
Lifetime 86.7a 87.1a 86.2 85.7 86.5 85.2 85.6 88.4b 87.6 87.2 87.1 87.0 86.0 86.4
Past Year 77.9 78.1 78.0 77.9 78.8 77.9 78.0 83.9 82.3 83.1 82.8 83.2 82.8 82.5
Past Month 60.5 61.4 60.5 60.9 61.9 61.2 61.2 67.7 66.3 67.3 66.8 67.0 67.4  67.4
Cigarettes                            
Lifetime 71.2a 70.2a 68.7a 67.3a 66.6a 64.7 64.2 -- -- -- -- -- -- --
Past Year 49.0a 47.6a 47.5a 47.2a 47.0a 45.1 45.0 41.8b 40.8b 41.4b 40.2b 37.1 36.2 35.4
Past Month 40.8a 40.2a 39.5a 39.0a 38.4a 36.2 35.7 31.4b 29.5b 30.2b 28.7b 26.7 25.7 24.3

End Notes

1 RTI International is a trade name of Research Triangle Institute.

2 See http://webapp.icpsr.umich.edu/cocoon/SAMHDA/DAS3/00064.xml.

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