A variety of surveys and data systems other than the National Survey on Drug Use and Health (NSDUH) collect data on substance use and mental health problems. It is useful to consider the results of these other studies when discussing NSDUH data. This Appendix briefly describes one of these other data systems that publish State estimates, presenting selected comparisons with NSDUH results. The State-level survey that collects data on substance use discussed in this appendix is the Behavioral Risk Factor Surveillance System (BRFSS), sponsored by the Centers for Disease Control and Prevention (CDC). Another CDC data system that provides State-level substance use estimates for most but not all States is the Youth Risk Behavior Survey (YRBS). Differences between the YRBS and NSDUH sampling designs, and age groups used in NSDUH small area estimates, imply that comparisons of prevalence rates are not straightforward. However, ignoring these differences and examining estimates at a national level, the YRBS has generally shown to have higher prevalence rates but similar long-term trends compared with NSDUH (Center for Behavioral Health Statistics and Quality [CBHSQ], 2011). For further details about the YRBS, see the CDC Web site at http://www.cdc.gov/HealthyYouth/yrbs/index.htm.
When considering the information presented here, it is important to understand the methodological differences between these surveys and the impact that these differences could have on estimates of substance use. Several studies have compared NSDUH estimates with estimates from other studies and have evaluated how differences may have been affected by differences in survey methodology (Brener et al., 2006; Gfroerer, Wright, & Kopstein, 1997; Grucza, Abbacchi, Przybeck, & Gfroerer, 2007; Hennessy & Ginsberg, 2001; Miller et al., 2004). These studies suggest that the goals and approaches of surveys are often different, making comparisons between them difficult. Some methodological differences that have been identified as affecting comparisons include populations covered, sampling methods, mode of data collection, survey setting, questionnaires, and estimation methods.
BRFSS is a State-based system of health surveys that collect information on health risk behaviors (including cigarette and alcohol use), preventive health practices, and health care access primarily related to chronic disease and injury. BRFSS is an annual, State-based telephone (landline only) survey of the civilian, noninstitutionalized adult population aged 18 or older and is sponsored by the CDC. In 2010, BRFSS collected data from all 50 States, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, and Guam using a computer-assisted telephone interviewing (CATI) design. More than 400,000 adults are interviewed each year. State estimates are presented on a yearly basis. BRFSS data are weighted based on the probability of selection of a telephone number, the number of adults in a household, and the number of telephones in a household. A final poststratification adjustment is made for nonresponse and noncoverage of households without telephones. The BRFSS State prevalence rates and confidence intervals presented in this report (in Tables D.1 and D.2 at the end of this appendix) are weighted design-based estimates (i.e., each respondent is weighted, and the survey design is accounted for in the estimates) from the 2010 survey. To address the increasing number of cell phone-only households, 48 States, the District of Columbia, Guam, Puerto Rico, and Virgin Islands collected a sample of cell phone-only interviews in a pilot study in 2010 to reach this portion of the population. However, data collected from cell phone-only households have not been incorporated into the regular BRFSS surveys. For more details about BRFSS, see the CDC Web site at http://www.cdc.gov/brfss.
There are three measures for which State estimates are produced for both BRFSS and NSDUH: past month alcohol use, past month binge alcohol use, and cigarette use ("past month" use for NSDUH and "current" use for BRFSS). Past month alcohol use is defined consistently in both BRFSS and NSDUH as having an alcoholic beverage in the past month. In NSDUH, past month cigarette use is defined as having smoked part or all of a cigarette during the past 30 days. In BRFSS, the cigarette use measure reported is current cigarette use, which is defined as having smoked at least 100 cigarettes during the lifetime and indicating smoking every day or some days at the time of the survey. Because of these subtle but present differences in definitions, the NSDUH estimates tend to be higher in that they catch 2 groups of people that the BRFSS estimates would not: (1) respondents who have not smoked 100 cigarettes in their lifetime but had smoked in the past month, and (2) respondents who had smoked a cigarette earlier in the month but were not smoking at the time of the survey. Lastly, both surveys ask about binge alcohol use in the past month. The definition for binge alcohol use in NSDUH is having had five or more drinks of an alcoholic beverage on the same occasion (i.e., at the same time or within a couple hours of each other) on at least 1 day in the past 30 days. In BRFSS, women are asked about drinking four or more drinks on one occasion, whereas men are asked about drinking five or more drinks on one occasion.
In this appendix, the findings of the 2010 BRFSS State estimates and the combined 2009-2010 NSDUH State estimates for past month alcohol use and cigarette use ("past month" use for NSDUH and "current" use for BRFSS) are presented. In Tables D.1 and D.2, the 2010 BRFSS State estimates for adults aged 18 or older are shown alongside the pooled 2009-2010 NSDUH small area estimates for the same age group (by combining the 18 to 25 and 26 or older age groups). Table D.1 also includes p values that indicate whether the BRFSS and NSDUH estimates are significantly different from each other for a given State using an exact test described in Section D.1. As can be seen in Table D.2, the NSDUH past month cigarette use estimates tend to be higher than the current cigarette use estimates from BRFSS; no p values of differences are shown. Because the definitions for binge alcohol use in the two surveys are different for women, no comparison of binge alcohol use was done.
The method for comparing the two estimates is similar to what is described in Section A.12 of Appendix A. Here, the null hypothesis of no difference is tested, that is, 
(where 
is a State-specific BRFSS direct prevalence
rate and 
is a State-specific NSDUH model-based prevalence rate) or equivalently that the logs-odds ratio is zero, that is, 
, where 
is defined as 
, where ln denotes the natural logarithm. An estimate of is given by 
, where 
and 
are the 2010 BRFSS
State estimates and the 2009-2010 NSDUH State estimates, respectively (as given in Tables D.1 and D.2). To compute the variance of 
, that is, 
, let 
and 
, then 
. The covariance term can be assumed to be zero because the BRFSS and NSDUH samples are independent.
The quantity 
can be obtained by using the 95 percent Bayesian confidence intervals in Tables D.1 and D.2. For this purpose, let (
) denote the 95 percent Bayesian confidence interval for a given State-s:
, D
where 
.
The quantity 
can be obtained by using the 95 percent confidence intervals in Tables D.1 and D.2. For this purpose, let (
) denote the 95 percent confidence intervals for a given State-s. Using the first-order Taylor series approximation, the variance can be calculated as follows:
. D
The p value (given in Table D.1) for testing the null hypothesis of no difference () is given by 
, where 
is a standard normal random variate, 
, and 
denotes the absolute value of 
.
As can be seen in Table D.1, for past month alcohol use, the NSDUH and the BRFSS estimates for about half of the States are similar (i.e., at the 5 percent level of significance, 25 of 51 States are different). These estimates are also highly correlated (correlation coefficient = 0.93). Figures D.1 and D.2 were created by using the BRFSS State estimates and the NSDUH State estimates and categorizing the States into five quintiles similar to the process described in Section 1.2 of Chapter 1. Note that in Tables D.1 and D.2, the BRFSS estimates and corresponding confidence intervals are rounded to one decimal place, whereas the NSDUH small area estimates and Bayesian confidence intervals are rounded to two decimal places. Therefore, all of the tables and maps included in this appendix use that approximation.
As can be seen in Figures D.1 and D.2, 7 out of 10 States with the highest rates of alcohol use (States shown in red) were the same in the two surveys: Connecticut, District of Columbia, Massachusetts, New Hampshire, Rhode Island, Vermont, and Wisconsin. The lowest rate of past month alcohol use was in Utah for the both the BRFSS survey and NSDUH (see Table D.1 and Figures D.1 and D.2).
As can be seen in Table D.2, the NSDUH estimates of past month cigarette use are always larger than the BRFSS estimates of current cigarette use. Some of this difference is the result of the differences in definitions as discussed earlier in this appendix; thus, exact tests to examine significant differences between the NSDUH and BRFSS cigarette use estimates are not included. Although the NSDUH estimates are consistently larger for all 50 States and the District of Columbia, these 2 sets of estimates are highly correlated (correlation coefficient = 0.90).
Figures D.3 and D.4 were created using the same method used to produce Figures D.1 and D.2. As can be seen in Figures D.3 and D.4, 6 out of 10 States with the highest rates of cigarette use (States shown in red) were the same in the 2 surveys: Alabama, Arkansas, Kentucky, Mississippi, Oklahoma, and West Virginia. The lowest rate of cigarette use for both surveys occurred in Utah (see Table D.2).
The BRFSS estimates are design based; however, the NSDUH estimates are model based. Also, the NSDUH estimates are based on the pooled 2009 and 2010 NSDUHs (2 years of data), whereas the BRFSS estimates are based on the 2010 BRFSS survey (1 year of data). Although the BRFSS estimates are only based on 1 year of data, the BRFSS sample sizes for a given State are in general much larger than the sample sizes for NSDUH over 2 years. The 8 "large" States17 (California, Florida, Illinois, Michigan, New York, Ohio, Pennsylvania, and Texas) have a sample size of approximately 7,200 respondents each for the 2009-2010 combined NSDUH data. In 2009-2010, sample sizes in these States ranged from 5,900 to 7,375 (see Table A.9 in Appendix A). For the 2010 BRFSS, 1 State (Illinois) had a slightly smaller sample size as compared with the NSDUH data, but the other 7 States had larger sample sizes. Overall, the BRFSS sample sizes for the 8 "large" States varied from a low of 5,202 respondents in Illinois to a high of 35,109 respondents in Florida, with a median sample size of 10,547.18 For the remaining 43 small sample States, the NSDUH sample size for the combined 2009-2010 data was approximately 1,800 respondents for each State. The BRFSS sample sizes for the small sample States were much larger, varying from a low of 1,964 respondents in Alaska to a high of 19,628 respondents in Washington, with a median sample size of 6,798. Sample size differences of this magnitude explain why the NSDUH Bayesian confidence intervals are generally wider than the corresponding BRFSS design-based confidence intervals.
| State | 2010 BRFSS (Estimate) |
2010 BRFSS (95% Confidence Interval) |
2009-2010 NSDUH (Estimate) |
2009-2010 NSDUH (95% Confidence Interval) |
P Value |
|---|---|---|---|---|---|
| NOTE: NSDUH estimates along with 95 percent Bayesian confidence (credible) intervals are based on a survey-weighted hierarchical Bayes estimation approach and are generated by Markov Chain Monte Carlo techniques. BRFSS estimates are based on a survey-weighted direct estimation approach. NOTE: p value: Probability of no difference between the BRFSS and NSDUH estimates. Source: SAMHSA, Center for Behavioral Health Statistics and Quality, National Survey on Drug Use and Health, 2009-2010 (Revised March 2012); CDC, Behavioral Risk Factor Surveillance System, 2010. |
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| Alabama | 37.5 | (35.8 - 39.2) | 46.41 | (42.90 - 49.95) | 0.000 |
| Alaska | 58.4 | (54.9 - 62.0) | 57.44 | (53.54 - 61.24) | 0.719 |
| Arizona | 51.7 | (49.2 - 54.1) | 51.97 | (47.93 - 55.99) | 0.909 |
| Arkansas | 38.4 | (36.0 - 40.9) | 44.16 | (40.54 - 47.85) | 0.010 |
| California | 53.3 | (52.2 - 54.4) | 54.50 | (52.38 - 56.61) | 0.324 |
| Colorado | 58.4 | (56.9 - 59.8) | 67.27 | (63.58 - 70.77) | 0.000 |
| Connecticut | 66.1 | (64.3 - 67.8) | 63.79 | (59.93 - 67.48) | 0.272 |
| Delaware | 59.3 | (57.1 - 61.4) | 60.72 | (56.81 - 64.49) | 0.530 |
| District of Columbia | 62.7 | (60.7 - 64.8) | 65.03 | (61.47 - 68.44) | 0.262 |
| Florida | 55.3 | (54.0 - 56.5) | 54.13 | (52.00 - 56.25) | 0.354 |
| Georgia | 47.7 | (45.8 - 49.6) | 51.97 | (48.18 - 55.75) | 0.048 |
| Hawaii | 49.0 | (47.1 - 50.8) | 51.20 | (47.41 - 54.97) | 0.307 |
| Idaho | 44.4 | (42.7 - 46.2) | 51.55 | (47.89 - 55.19) | 0.001 |
| Illinois | 59.1 | (57.1 - 61.1) | 58.67 | (56.67 - 60.65) | 0.768 |
| Indiana | 47.2 | (45.7 - 48.7) | 53.48 | (49.85 - 57.07) | 0.002 |
| Iowa | 55.4 | (53.6 - 57.2) | 60.29 | (56.59 - 63.87) | 0.020 |
| Kansas | 52.4 | (50.9 - 53.9) | 59.93 | (56.29 - 63.46) | 0.000 |
| Kentucky | 40.9 | (38.9 - 42.9) | 41.74 | (38.27 - 45.29) | 0.685 |
| Louisiana | 48.9 | (47.2 - 50.6) | 50.38 | (46.69 - 54.06) | 0.476 |
| Maine | 57.2 | (55.7 - 58.6) | 60.18 | (56.59 - 63.66) | 0.130 |
| Maryland | 54.6 | (53.0 - 56.2) | 56.03 | (52.00 - 59.98) | 0.516 |
| Massachusetts | 65.6 | (64.4 - 66.8) | 68.30 | (64.97 - 71.45) | 0.133 |
| Michigan | 55.7 | (54.1 - 57.2) | 59.27 | (57.19 - 61.32) | 0.007 |
| Minnesota | 59.6 | (57.6 - 61.6) | 63.62 | (59.92 - 67.15) | 0.060 |
| Mississippi | 36.1 | (34.3 - 37.8) | 44.40 | (40.88 - 47.97) | 0.000 |
| Missouri | 47.7 | (45.4 - 50.0) | 54.51 | (50.83 - 58.14) | 0.002 |
| Montana | 57.0 | (55.0 - 59.0) | 61.89 | (58.17 - 65.48) | 0.023 |
| Nebraska | 59.0 | (57.3 - 60.7) | 55.97 | (52.21 - 59.67) | 0.146 |
| Nevada | 56.7 | (53.9 - 59.4) | 58.98 | (54.96 - 62.87) | 0.356 |
| New Hampshire | 64.3 | (62.7 - 66.0) | 68.42 | (64.85 - 71.78) | 0.040 |
| New Jersey | 56.2 | (54.9 - 57.6) | 59.98 | (56.30 - 63.55) | 0.058 |
| New Mexico | 48.5 | (46.7 - 50.4) | 49.16 | (45.32 - 53.01) | 0.761 |
| New York | 58.2 | (56.9 - 59.6) | 59.53 | (57.37 - 61.65) | 0.306 |
| North Carolina | 44.1 | (42.6 - 45.5) | 52.82 | (49.15 - 56.46) | 0.000 |
| North Dakota | 58.5 | (56.4 - 60.6) | 64.08 | (60.49 - 67.52) | 0.009 |
| Ohio | 53.2 | (51.7 - 54.7) | 56.90 | (54.78 - 58.99) | 0.005 |
| Oklahoma | 40.0 | (38.5 - 41.6) | 50.69 | (46.73 - 54.64) | 0.000 |
| Oregon | 58.2 | (56.1 - 60.3) | 65.33 | (61.76 - 68.72) | 0.001 |
| Pennsylvania | 54.2 | (52.9 - 55.6) | 59.18 | (56.86 - 61.46) | 0.000 |
| Rhode Island | 62.7 | (60.8 - 64.5) | 65.47 | (61.44 - 69.29) | 0.217 |
| South Carolina | 42.6 | (40.6 - 44.5) | 49.51 | (45.81 - 53.23) | 0.001 |
| South Dakota | 58.2 | (56.3 - 60.0) | 62.30 | (58.55 - 65.90) | 0.054 |
| Tennessee | 28.2 | (26.1 - 30.3) | 43.39 | (39.60 - 47.26) | 0.000 |
| Texas | 49.9 | (48.4 - 51.5) | 53.48 | (51.36 - 55.58) | 0.008 |
| Utah | 25.0 | (23.8 - 26.2) | 28.93 | (25.78 - 32.31) | 0.022 |
| Vermont | 63.9 | (62.3 - 65.5) | 65.78 | (62.20 - 69.18) | 0.343 |
| Virginia | 54.1 | (51.3 - 56.8) | 55.94 | (52.25 - 59.58) | 0.431 |
| Washington | 59.3 | (58.3 - 60.4) | 61.33 | (57.66 - 64.88) | 0.294 |
| West Virginia | 27.6 | (25.7 - 29.5) | 42.64 | (38.95 - 46.42) | 0.000 |
| Wisconsin | 66.0 | (63.8 - 68.1) | 69.00 | (65.58 - 72.23) | 0.142 |
| Wyoming | 51.0 | (49.1 - 52.9) | 56.62 | (52.84 - 60.33) | 0.009 |
| State | 2010 BRFSS1 (Estimate) |
2010 BRFSS1 (95% Confidence Interval) |
2009-2010 NSDUH2 (Estimate) |
2009-2010 NSDUH2 (95% Confidence Interval) |
|---|---|---|---|---|
| NOTE: NSDUH estimates along with 95 percent Bayesian confidence (credible) intervals are based on a survey-weighted hierarchical Bayes estimation approach and are generated by Markov Chain Monte Carlo techniques. BRFSS estimates are based on a survey-weighted direct estimation approach. 1 BRFSS respondents were classified as current smokers if they reported having smoked at least 100 cigarettes during their lifetime and indicated that they smoked every day or some days at the time of the survey. 2 NSDUH respondents were classified as past month cigarette users if they smoked all or part of a cigarette during the past 30 days. Source: SAMHSA, Center for Behavioral Health Statistics and Quality, National Survey on Drug Use and Health, 2009-2010 (Revised March 2012); CDC, Behavioral Risk Factor Surveillance System, 2010. |
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| Alabama | 21.9 | (20.4 - 23.4) | 29.00 | (26.33 - 31.83) |
| Alaska | 20.4 | (17.3 - 23.4) | 28.34 | (25.32 - 31.56) |
| Arizona | 15.0 | (13.3 - 16.8) | 23.78 | (21.10 - 26.68) |
| Arkansas | 22.9 | (20.6 - 25.2) | 30.10 | (27.27 - 33.09) |
| California | 12.1 | (11.4 - 12.8) | 19.88 | (18.42 - 21.43) |
| Colorado | 16.0 | (14.9 - 17.1) | 22.41 | (19.95 - 25.09) |
| Connecticut | 13.2 | (11.8 - 14.6) | 22.64 | (20.01 - 25.50) |
| Delaware | 17.3 | (15.5 - 19.1) | 25.08 | (22.40 - 27.98) |
| District of Columbia | 15.6 | (14.1 - 17.2) | 24.63 | (21.86 - 27.62) |
| Florida | 17.1 | (16.1 - 18.1) | 23.70 | (22.17 - 25.30) |
| Georgia | 17.6 | (16.0 - 19.2) | 23.96 | (21.25 - 26.89) |
| Hawaii | 14.5 | (13.2 - 15.8) | 20.94 | (18.44 - 23.67) |
| Idaho | 15.7 | (14.3 - 17.0) | 25.44 | (22.88 - 28.18) |
| Illinois | 16.9 | (15.3 - 18.5) | 26.11 | (24.62 - 27.66) |
| Indiana | 21.2 | (19.9 - 22.5) | 27.67 | (25.05 - 30.45) |
| Iowa | 16.1 | (14.8 - 17.5) | 26.96 | (24.25 - 29.85) |
| Kansas | 17.0 | (15.8 - 18.2) | 25.40 | (22.92 - 28.06) |
| Kentucky | 24.8 | (23.1 - 26.5) | 31.88 | (28.95 - 34.96) |
| Louisiana | 22.1 | (20.6 - 23.6) | 27.83 | (25.01 - 30.84) |
| Maine | 18.2 | (17.0 - 19.5) | 26.16 | (23.49 - 29.01) |
| Maryland | 15.2 | (14.0 - 16.5) | 21.02 | (18.40 - 23.91) |
| Massachusetts | 14.1 | (13.2 - 15.0) | 21.87 | (19.57 - 24.37) |
| Michigan | 18.9 | (17.7 - 20.2) | 27.71 | (26.17 - 29.32) |
| Minnesota | 14.9 | (13.5 - 16.3) | 24.69 | (22.23 - 27.34) |
| Mississippi | 22.9 | (21.4 - 24.5) | 29.49 | (26.73 - 32.42) |
| Missouri | 21.1 | (19.2 - 22.9) | 29.11 | (26.36 - 32.03) |
| Montana | 18.8 | (17.1 - 20.5) | 26.21 | (23.64 - 28.95) |
| Nebraska | 17.2 | (15.8 - 18.7) | 25.68 | (23.10 - 28.44) |
| Nevada | 21.3 | (19.1 - 23.6) | 25.48 | (22.60 - 28.60) |
| New Hampshire | 16.9 | (15.5 - 18.2) | 25.60 | (22.98 - 28.41) |
| New Jersey | 14.4 | (13.4 - 15.4) | 22.63 | (20.05 - 25.43) |
| New Mexico | 18.5 | (16.8 - 20.1) | 23.92 | (21.37 - 26.68) |
| New York | 15.5 | (14.4 - 16.5) | 22.53 | (21.06 - 24.08) |
| North Carolina | 19.8 | (18.5 - 21.1) | 27.89 | (25.10 - 30.87) |
| North Dakota | 17.4 | (15.7 - 19.1) | 23.94 | (21.47 - 26.60) |
| Ohio | 22.5 | (21.2 - 23.9) | 27.35 | (25.76 - 29.00) |
| Oklahoma | 23.7 | (22.3 - 25.0) | 30.95 | (27.93 - 34.14) |
| Oregon | 15.1 | (13.5 - 16.7) | 25.35 | (22.79 - 28.10) |
| Pennsylvania | 18.4 | (17.4 - 19.5) | 26.53 | (24.89 - 28.23) |
| Rhode Island | 15.7 | (14.3 - 17.1) | 24.66 | (22.05 - 27.48) |
| South Carolina | 21.0 | (19.1 - 22.8) | 28.31 | (25.44 - 31.37) |
| South Dakota | 15.4 | (14.0 - 16.8) | 26.71 | (23.93 - 29.68) |
| Tennessee | 20.1 | (18.3 - 21.8) | 29.73 | (26.79 - 32.84) |
| Texas | 15.8 | (14.6 - 17.0) | 23.72 | (22.19 - 25.32) |
| Utah | 9.1 | (8.2 - 10.0) | 17.17 | (14.85 - 19.78) |
| Vermont | 15.4 | (14.1 - 16.6) | 23.57 | (21.05 - 26.28) |
| Virginia | 18.5 | (16.0 - 21.0) | 24.21 | (21.76 - 26.85) |
| Washington | 15.2 | (14.4 - 16.0) | 24.17 | (21.74 - 26.76) |
| West Virginia | 26.8 | (25.0 - 28.6) | 33.86 | (30.71 - 37.15) |
| Wisconsin | 19.1 | (17.0 - 21.1) | 24.96 | (22.46 - 27.65) |
| Wyoming | 19.5 | (18.0 - 21.1) | 26.98 | (24.29 - 29.84) |
Below is a map; click here for the text describing this map.
Source: Centers for Disease Control and Prevention (CDC), Behavioral Risk Factor Surveillance System Survey, 2010.
Below is a map; click here for the text describing this map.
Source: SAMHSA, Center for Behavioral Health Statistics and Quality, NSDUH, 2009 and 2010 (Revised March 2012).
Below is a map; click here for the text describing this map.
Source: Centers for Disease Control and Prevention (CDC), Behavioral Risk Factor Surveillance System Survey, 2010.
Below is a map; click here for the text describing this map.
Source: SAMHSA, Center for Behavioral Health Statistics and Quality, NSDUH, 2009 and 2010 (Revised March 2012).
17 The eight most populous States are referenced as the "large" States in this report.
18 For more information, see http://www.cdc.gov/brfss/technical_infodata/surveydata/2010.htm.
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