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2004 National Survey on Drug Use & Health:  Overview

Overview of Findings from the 2004 National Survey on Drug Use and Health

REVISIONS AS OF 9/8/2005

Several updates have been incorporated into this report since it was published. These changes were made in the Web documents and are listed below, indicating the relevant page and paragraph in the published hard copy.

In several places, the published version of this report indicates that 2004 estimates are similar to 2002 estimates. However, statistical testing indicates a significant difference between 2004 and 2002, so the text in this updated Web document was revised to remove the reference to no change from the 2002 data. This occurs on the following pages in the published version: page 3 in bullet 3; page 4 in bullet 1; page 10 in paragraphs 2 and 3; and page 15 in paragraph 2.

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

Acknowledgments

This report was prepared by the Division of Population Surveys, Office of Applied Studies, SAMHSA, and by RTI International, a trade name of Research Triangle Institute, Research Triangle Park, North Carolina. Work by RTI was performed under Contract No. 283-03-9028. Contributors and reviewers at RTI listed alphabetically include Jeremy Aldworth, Katherine R. Bowman, Walter R. Boyle, Allison Burns, Sara L. Calvin, Jessica Duncan Cance, Patrick Chen, James R. Chromy, Andrew Clarke, Elizabeth Copello, David B. Cunningham, Teresa R. Davis, Steven L. Emrich, Ralph E. Folsom, Jr., Misty Foster, G. G. Frick, Eric A. Grau, David C. Heller, Erica Hirsch, Susan Hunter, B. Kathleen Jordan, Larry A. Kroutil, Judith T. Lessler, Bing Liu, Mary Ellen Marsden, Peilan Martin, Breda Munoz, Christine Murtha, Scott Novak, Lisa E. Packer, Michael R. Pemberton, Lanny Piper, Jeremy Porter, Tania Robbins, Kathryn Spagnola, Thomas G. Virag (Project Director), Michael Vorburger, Jill Webster, Matthew Westlake, and Li-Tzy Wu. Contributors at SAMHSA listed alphabetically, with chapter authorship noted, include Peggy Barker (Chapter 8), James Colliver (Chapters 4 and 6), Joan Epstein (Chapters 7 and 8), Joseph Gfroerer (Chapters 1, 2, 5, and 9), Joe Gustin, Arthur Hughes (Project Officer), Joel Kennet (Chapter 3), Sharon Larson (Chapters 7 and 8), Pradip Muhuri, Dicy Painter, and Doug Wright (Chapter 6). At RTI, Richard S. Straw edited the report with assistance from Jason Guder and Claudia Clark. Also at RTI, Diane G. Eckard and Danny Occoquan prepared the graphics; Brenda K. Porter and Tracy Woodall formatted the tables; Joyce Clay-Brooks, Debbie Bond, and Judy Cannada formatted and word processed the report; and Pamela Couch Prevatt, Teresa F. Gurley, Kim Cone, David Belton, and Shari B. Lambert prepared its press and Web versions. Final report production was provided by Beatrice A. Rouse, Coleen Sanderson, and Jane Feldmann at SAMHSA.

Public Domain Notice

All material appearing in this report is in the public domain and may be reproduced or copied without permission from the Substance Abuse and Mental Health Services Administration. However, this publication may not be reproduced or distributed for a fee without specific, written authorization of the Office of Communications, SAMHSA, U.S. Department of Health and Human Services. Citation of the source is appreciated. Suggested citation:

Substance Abuse and Mental Health Services Administration. (2005). Overview of Findings from the 2004 National Survey on Drug Use and Health (Office of Applied Studies, NSDUH Series H-27, DHHS Publication No. SMA 05-4061). Rockville, MD.

Obtaining Copies of Publications from SAMHSA's Office of Applied Studies

Web Access:  http://samhsa.gov/data/

Originating Office:  SAMHSA, Office of Applied Studies
 

September 2005

 

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2004 National Survey on Drug Use & Health:  Overview

Table of Contents (TOC)

Note:  If interested in printing the contents of this overview, we recommend that the PDF format of Overview be used.  If interested in the full report, click here for the full report.

If comparing the web version to the published hard copy, please note that the web version is the most up-to-date.  Several updates have been incorporated into this report since the hard copy was published. These changes were made in the PDF and HTML Web documents and are listed in the Table of Contents (TOC) indicating the relevant page and paragraph in the published report.  The updates include the following:  In several places, the published version of this report indicates that 2004 estimates are similar to 2002 estimates. However, statistical testing indicates a significant difference between 2004 and 2002, so the text in this updated Web document was revised to remove the reference to no change from the 2002 data.  In the PDF version, this update occurs on page 3 in bullet 3; page 4 in bullet 1; page 10 in paragraphs 2 and 3; and page 15 in paragraph 2.  In addition, some spellings were corrected.

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1. Introduction
     Highlights of Findings (page 3: bullet 3 & page 4: bullet 1, revised 9/8/05)

2. Illicit Drug Use (page 10: paragraphs 2 & 3, revised 9/8/05)

3. Alcohol Use (page 15: paragraph 2, revised 9/8/05)

4. Tobacco Use

5. Initiation of Substance Use

6. Youth Prevention-Related Measures

7. Substance Dependence, Abuse, and Treatment

8. Prevalence and Treatment of Mental Health Problems

9. Discussion of Trends in Substance Use Prevalence

References

Appendix: Prevalence Estimate Tables

National Findings Report and Detailed Tables from the 2004 NSDUH

Available at SAMHSA's website:
     http://www.oas.samhsa.gov/nsduh.htm
     http://www.oas.samhsa.gov

 

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1. Introduction

This report presents the first information from the 2004 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. Prior to 2002, the survey was called the National Household Survey on Drug Abuse (NHSDA). This Overview report provides a concise summary of the main results of the 2004 NSDUH. A more complete presentation of the initial results and methodology of the survey is given in the full report, Results from the 2004 National Survey on Drug Use and Health: National Findings (Office of Applied Studies [OAS], 2005). Both reports present 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 included. State-level and SubState-level estimates from NSDUH will be presented in separate reports.

A major focus of this report is changes in substance use between 2003 and 2004. Trends since 2002 also are discussed. Because of improvements to the survey in 2002, the 2002 data constitute a new baseline for tracking trends in substance use and other measures. Therefore, estimates from the 2002, 2003, and 2004 NSDUHs should not be compared with estimates from the 2001 and earlier NSDUHs to assess changes in substance use and mental health problems over time. A discussion of long-term trends is included in the final chapter of this report.

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 their places of residence. The survey is sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA) of the U.S. Department of Health and Human Services and is planned and managed by SAMHSA's OAS. Data collection is conducted under contract with RTI International, Research Triangle Park, North Carolina.1

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

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 means of responding to questions 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).

Consistent with the 2002 and 2003 surveys, the 2004 NSDUH employed a 50-State sample design with an independent, multistage area probability sample for each of the 50 States and the District of Columbia to facilitate State-level estimation. The design also oversampled youths and young adults, so that each State's sample was approximately equally distributed among three major age groups: 12 to 17 years, 18 to 25 years, and 26 years or older.

Nationally, 130,130 addresses were screened for the 2004 survey, and 67,760 interviews were completed. The survey was conducted from January through December 2004. Weighted response rates for household screening and for interviewing were 90.9 and 77.0 percent, respectively.

1.2. Trend Measurement

Although the design of the 2002, 2003, and 2004 NSDUHs is similar to the design of the 1999 through 2001 surveys, there are important methodological differences that have an impact on the comparability of the 2002-2004 estimates with estimates from prior surveys. In addition to the name change, each NSDUH respondent is now given an incentive payment of $30. These changes, both implemented in 2002 and continued in 2003 and 2004, resulted in a substantial improvement in the survey response rate. The changes also affected respondents' reporting of many critical items that are the basis of prevalence measures reported by the survey each year. Comparability also could be affected by improved data collection quality control procedures that were introduced beginning in 2001 and by incorporation of new population data from the 2000 decennial census into NSDUH sample weighting procedures. Analyses of the effects of each 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.

Limited trend assessment can be done using information on prior substance use collected in the 2002-2004 NSDUHs. Specifically, questions on age at first use of substances, in conjunction with respondents' ages and interview dates, provide data that can be used to estimate the rates of first-time use (incidence) for years prior to 2002. Trends for 1965 to 2003 in these incidence measures for youths and young adults have been estimated. However, these estimates should be interpreted cautiously because they may be subject to significant bias due to long recall periods (Gfroerer, Hughes, Chromy, Heller, & Packer, 2004). New measures of recent patterns and trends in substance use initiation are included in Chapter 5 of this report. Long-term trends in some key measures of substance use, such as marijuana and cocaine, are assessed in Chapter 9 using data from prior NSDUHs by separately examining trends within periods during which the survey data are comparable. These periods are 1971-1998, 1999-2001, and 2002-2004.

1.3. Purpose of This Report and Availability of Other Reports

This Overview report is intended to provide a concise summary of the key results from the 2004 NSDUH. It contains a subset of the results given in the full report, Results from the 2004 National Survey on Drug Use and Health: National Findings (OAS, 2005). Both reports present the results in separate chapters that discuss the national findings on seven topics: use of illicit drugs; use of alcohol; use of tobacco products; trends in initiation of substance use; prevention-related issues; substance dependence, abuse, and treatment; and mental health. A final chapter discusses trends. The full report also includes appendices that provide details on the survey methodology and statistical methods and measurement, offer key NSDUH definitions, discuss other sources of related data, list the references cited in the report (as well as other relevant references), and present selected tabulations of estimates. This overview report includes several tables in an appendix.

An extensive set of tables, including standard errors, is available upon request from OAS or through the Internet at http://www.oas.samhsa.gov. Tables included in the appendix of this overview report can be mapped back to the more extensive set of tables on the Internet by using the table number in parentheses in the upper left corner of each table (e.g., Table A.1 in the appendix is Table 1.1A REV 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://www.oas.samhsa.gov). In addition, OAS makes public use data files available to researchers through the Substance Abuse and Mental Health Data Archive (SAMHDA, 2005). Currently, files are available from the 1979 to 2003 surveys at http://www.icpsr.umich.edu/SAMHDA/index.html. The NSDUH 2004 public use file will be available by the end of 2005.

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2004 National Survey on Drug Use & Health:  Overview

1.4. Highlights of Findings

This Overview report includes a summary of the key findings that are discussed in the full report. Highlights of these findings are given below.

Illicit Drug Use

Alcohol Use

Tobacco Use

Initiation of Substance Use (Incidence)

Youth Prevention-Related Measures

Substance Dependence, Abuse, and Treatment

Illicit Drug Use Treatment Need

Major Depressive Episode

Serious Psychological Distress

Treatment for Any Mental Health Problem

 

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2. Illicit Drug Use

The National Survey on Drug Use and Health (NSDUH) obtains information on nine different categories of illicit drug use: any 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, mushrooms, and "Ecstasy" (MDMA). Inhalants include a variety of substances, such as amyl nitrite, cleaning fluids, gasoline, paint, and glue. The four categories of prescription-type drugs (pain relievers, tranquilizers, stimulants, and sedatives) cover numerous drugs available through prescriptions as well as drugs within these groupings that may be manufactured illegally, such as methamphetamine, which is included under stimulants. Respondents are asked to report only uses of drugs that were not prescribed for them or drugs they took only for the experience or feeling they caused; therefore, over-the-counter drugs and legitimate uses 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.

Prevalence, by Type of Drug. In 2004, an estimated 19.1 million Americans aged 12 or older were current (past month) illicit drug users, meaning they had used an illicit drug during the month prior to the survey interview. This estimate represents 7.9 percent of the population aged 12 years old or older, similar to the rate in 2003 (8.2 percent) and in 2002 (8.3 percent). Marijuana was the most commonly used illicit drug, with 14.6 million past month users (6.1 percent of the population). An estimated 2.0 million persons (0.8 percent) were current cocaine users; of these, 467,000 used crack during the same time period (0.2 percent). Hallucinogens were used by 929,000 persons (0.4 percent). There were an estimated 166,000 current heroin users (0.1 percent). All of these estimates are similar to estimates for 2003.

An estimated 8.2 million people (3.4 percent of the population) were current users of illicit drugs other than marijuana in 2004. Most (6.0 million, 2.5 percent of the population) used psychotherapeutic drugs nonmedically. An estimated 4.4 million used pain relievers, 1.6 million used tranquilizers, 1.2 million used stimulants (including 583,000 methamphetamine users), and 0.3 million used sedatives. These estimates are all similar to the corresponding estimates for 2003.

The number of current Ecstasy users was the same in 2004 (450,000) as it had been in 2003 (470,000), after it had decreased between 2002 (676,000) and 2003. There were no significant changes in the past month use of other hallucinogens between 2003 and 2004.

There was no significant change in past month, past year, or lifetime nonmedical use of pain relievers among persons aged 12 or older between 2003 and 2004. The rate of past month use was 2.0 percent in 2003 and 1.8 percent in 2004.

Age. Rates of drug use showed substantial variation by age. For example, 3.8 percent of youths aged 12 or 13 reported current illicit drug use in 2004 (Figure 1). As in prior years, illicit drug use in 2004 tended to increase with age among young persons, peaking among 18 to 20 year olds (21.7 percent) and generally declining after that point with increasing age.

 

Figure 1. Past Month Illicit Drug Use among Persons Aged 12 or Older, by Age: 2004

Figure 1     D

Youths Aged 12 to 17. The rate of current illicit drug use among youths gradually declined between 2002 and 2004. The rate was 11.6 percent in 2002, 11.2 percent in 2003, and 10.6 percent in 2004 (Figure 2). This represents a statistically significant change between 2002 and 2004, but not between 2002 and 2003 or between 2003 and 2004.

 

Figure 2. Past Month Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2004

Figure 2     D

The rate of current marijuana use among youths was 8.2 percent in 2002, 7.9 percent in 2003, and 7.6 percent in 2004, indicating a steady but not statistically significant decline. Declines in past year and lifetime use of marijuana among youths from 2002 to 2004 were statistically significant. Between 2002 and 2004, past month marijuana use declined for male youths (9.1 percent in 2002, 8.6 percent in 2003, and 8.1 percent in 2004), but it remained level for female youths (7.2, 7.2, and 7.1 percent) during the same period. The trend in marijuana use was different across regions, with a decrease in the South, nonsignificant decreases in the Northeast and Midwest, and a nonsignificant increase in the West.

Young Adults Aged 18 to 25. Rates of current use of illicit drugs were highest for the young adult age group (18 to 25 years) at 19.4 percent, with 16.1 percent using marijuana, 6.1 percent using prescription-type drugs nonmedically, 2.1 percent using cocaine, and 1.5 percent using hallucinogens. There were no changes in past month use of any drugs among young adults between 2003 and 2004. However, declines between 2002 and 2004 occurred for marijuana (17.3 percent in 2002, 17.0 percent in 2003, and 16.1 percent in 2004) and hallucinogens (1.9, 1.7, and 1.5 percent, respectively). Past year use of Ecstasy among young adults declined from 5.8 percent in 2002 to 3.7 percent in 2003 and to 3.1 percent in 2004. Current nonmedical use of prescription-type drugs showed no signs of decreasing among young adults, remaining at 6.1 percent in 2004, compared with 6.0 percent in 2003 and 5.4 percent in 2002. There were increases in lifetime prevalence of use from 2002 to 2004 of several categories of pain relievers among those aged 18 to 25: Vicodin®, Lortab®, or Lorcet®; Percocet®, Percodan®, or Tylox®; hydrocodone products; OxyContin®; and oxycodone products (Figure 3).

 

Figure 3. Lifetime Nonmedical Use of Selected Pain Relievers among Young Adults Aged 18 to 25: 2002-2004

Figure 3     D

Race/Ethnicity. Rates of current illicit drug use varied significantly among the major racial/ethnic groups in 2004. The rate was highest among persons reporting two or more races (13.3 percent) and American Indians or Alaska Natives (12.3 percent). Rates were 8.1 percent for whites, 7.2 percent for Hispanics, and 8.7 percent for blacks. Asians had the lowest rate at 3.1 percent. Among youths aged 12 to 17, the rate of current illicit drug use was highest among American Indians or Alaska Natives (26.0 percent). Rates for other groups were 12.2 percent among those reporting two or more races, 11.1 percent among whites, 10.2 percent among Hispanics, 9.3 percent among blacks, and 6.0 percent among Asians.

Employment. Current employment status was correlated with rates of illicit drug use in 2004. An estimated 19.2 percent of unemployed adults aged 18 or older were current illicit drug users compared with 8.0 percent of those employed full time and 10.3 percent of those employed part time. These rates are all similar to the corresponding rates in 2003. Although the rate of drug use was higher among unemployed persons compared with those from other employment groups, most drug users were employed. Of the 16.4 million illicit drug users aged 18 or older in 2004, 12.3 million (75.2 percent) were employed either full or part time.

 

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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. Prior to the administration of the alcohol use questions, an extensive list of examples of the kinds of beverages included is given to respondents. 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 as consumption. For this report, estimates for the prevalence of alcohol use are reported primarily at the following three levels for males and females and all ages:

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

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) at least once in the past 30 days (includes heavy use).

Heavy use - Five or more drinks on the same occasion on at least 5 different days in the past 30 days.

Prevalence, by Level of Use. About half (50.3 percent) of Americans aged 12 or older reported being current drinkers of alcohol in 2004. This translates to an estimated 121 million people. An estimated 22.8 percent (55 million) participated in binge drinking, and 6.9 percent (17 million) were heavy drinkers. These figures are all similar to those of 2002 and 2003.

Age. Both binge and heavy drinking in 2004 were highest for the 18- to 25-year-old age group compared with other age groups, with the peak rate for both measures occurring at age 21. The rate of binge drinking was 41.2 percent for young adults aged 18 to 25 and 48.2 percent at age 21. Heavy alcohol use was reported by 15.1 percent of young adults aged 18 to 25 and by 19.2 percent of 21 year olds.

Underage Alcohol Use. In 2004, about 10.8 million persons aged 12 to 20 (28.7 percent) reported drinking alcohol in the past month. Nearly 7.4 million (19.6 percent) were binge drinkers, and 2.4 million (6.3 percent) were heavy drinkers. These figures were similar to the 2002 and 2003 estimates. More males than females aged 12 to 20 reported binge drinking (22.1 vs. 17.0 percent) and heavy drinking (8.2 vs. 4.3 percent). Among persons aged 12 to 20, past month alcohol use rates were 16.4 percent among Asians, 19.1 percent among blacks, 24.3 percent among American Indians or Alaska Natives, 26.4 percent among those reporting two or more races, 26.6 percent among Hispanics, and 32.6 percent among whites.

Pregnant Women. Among pregnant women aged 15 to 44, an estimated 11.2 percent reported past month alcohol use and 4.5 percent reported past month binge drinking. These rates were significantly lower than the rates for nonpregnant women of that age (52.8 and 23.3 percent, respectively). These estimates were based on data averaged over 2003 and 2004.

College Students. Young adults aged 18 to 22 enrolled full time in college were more likely than their peers not enrolled full time (i.e., part-time college students and persons not enrolled in college) to use alcohol, binge drink, and drink heavily. Past month use was reported by 62.4 percent of full-time college students compared with 55.7 percent of persons aged 18 to 22 who were not currently enrolled full time. Binge and heavy use rates for college students were 43.4 and 18.6 percent, respectively, compared with 39.4 and 13.5 percent, respectively, for other persons aged 18 to 22. There were no significant changes in rates of past month, binge, or heavy alcohol use between 2003 and 2004 among full-time college students aged 18 to 22.

Driving Under the Influence of Alcohol. In 2004, an estimated 13.5 percent of persons aged 12 or older drove under the influence of alcohol at least once in the past year. This percentage was similar to that reported in 2003. The 2004 estimate corresponds to approximately 32.5 million persons. Driving under the influence varied by age group in 2004. An estimated 10.2 percent of 16 or 17 year olds, 20.2 percent of 18 to 20 year olds, and 28.2 percent of 21 to 25 year olds reported driving under the influence of alcohol (Figure 4). Beyond age 25, these rates declined with increasing age. Males were nearly twice as likely as females (17.9 vs. 9.4 percent, respectively) to drive under the influence of alcohol.

 

Figure 4. Driving Under the Influence of Alcohol in the Past Year among Persons Aged 16 or Older, by Age: 2004

Figure 4     D

 

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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."

Prevalence for Different Tobacco Products. An estimated 70.3 million Americans aged 12 or older reported current (past month) use of a tobacco product in 2004. This represents 29.2 percent of the population in that age range. An estimated 59.9 million persons (24.9 percent of the population) were current cigarette smokers; 13.7 million (5.7 percent) smoked cigars; 7.2 million (3.0 percent) used smokeless tobacco; and 1.8 million (0.8 percent) smoked tobacco in pipes (Figure 5). These rates of current use were unchanged between 2003 and 2004, but between 2002 and 2004 past month use of a tobacco product declined from 30.4 to 29.2 percent, past month cigarette use decreased from 26.0 to 24.9 percent, and past month smokeless tobacco use decreased from 3.3 to 3.0 percent.

 

Figure 5. Past Month Tobacco Use among Persons Aged 12 or Older: 2002-2004

Figure 5     D

Age. Among age groups, young adults aged 18 to 25 had the highest rate of current use of a tobacco product (44.6 percent) and of each specific product. In 2004, the rates of past month use among young adults were 39.5 percent for cigarettes, 12.7 percent for cigars, 4.9 percent for smokeless tobacco, and 1.2 percent for pipe tobacco. Current use of cigarettes and smokeless tobacco by young adults did not change significantly between 2002 and 2004.

Among youths aged 12 to 17 in 2004, an estimated 3.6 million (14.4 percent) used a tobacco product in the past month, and 3.0 million (11.9 percent) used cigarettes. The rate of past month cigarette use among 12 to 17 year olds declined from 13.0 percent in 2002 to 11.9 percent in 2004 (the rate was 12.2 percent in 2003). Cigar use in the past month was reported by 4.8 percent of youths in 2004, and past month smokeless tobacco use was reported by 2.3 percent; these rates were unchanged from 2002 and 2003.

Gender. In 2004, current use of a tobacco product among persons aged 12 or older was reported by a higher percentage of males (35.7 percent) than females (23.1 percent). Males also had higher rates of past month use of each specific tobacco product compared with females: cigarette smoking (27.7 percent of males vs. 22.3 percent of females); cigar smoking (9.8 percent of males vs. 1.9 percent of females); and use of smokeless tobacco (5.8 percent of males vs. 0.3 percent of females). Among youths aged 12 to 17, current cigarette smoking in 2004 was more prevalent among females (12.5 percent) than males (11.3 percent). The rate for females in this age group declined from 13.6 percent in 2002 to 12.5 percent in 2003, then remained unchanged in 2004. Among 12- to 17-year-old males, the rate of current cigarette use was 12.3 percent in 2002, 11.9 percent in 2003, and 11.3 percent in 2004 (no significant change).

Pregnant Women. Among women aged 15 to 44, combined data for 2003 and 2004 indicated that 18.0 percent of those who were pregnant smoked cigarettes in the past month compared with 30.0 percent of those who were not pregnant. Rates of past month cigarette smoking were lower for pregnant than nonpregnant women among those aged 26 to 44 (11.7 vs. 29.1 percent) and among those aged 18 to 25 (28.0 vs. 36.3 percent). However, among those aged 15 to 17, the rate of cigarette smoking for pregnant women was higher than for nonpregnant women (26.0 vs. 19.6 percent), although the difference was not significant.

County Type. Rates of cigarette smoking were 28.4 percent in nonmetropolitan areas, 26.0 percent in small metropolitan areas, and 23.2 percent in large metropolitan areas. However, the lowest rate in 2004, 22.8 percent, was found for completely rural counties, and the highest, 29.3 percent, was in the urbanized portions of nonmetropolitan areas. In completely rural nonmetropolitan counties, current cigarette use among persons aged 12 or older declined from 31.8 percent in 2002 and 28.0 percent in 2003 to 22.8 percent in 2004. Use of smokeless tobacco in the past month among persons aged 12 or older was highest in completely rural counties (8.0 percent) and lowest in large metropolitan areas (1.7 percent)

Discontinuation of Cigarette Use among Lifetime Daily Smokers. A measure of "quitting" or "discontinuation" of cigarette smoking is the percentage of persons not using cigarettes in the past month among those who have ever smoked cigarettes daily in their lifetime. In 2004, an estimated 46.2 percent of the estimated 93.4 million lifetime daily smokers aged 12 or older had discontinued cigarette use as evidenced by not smoking cigarettes in the past month.

 

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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 in the assessment of the effectiveness of current prevention programs and in determining where prevention efforts need to focus.

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 initiation based on questions on age and month at first use. Using this information, along with the interview date and the respondent's date of birth, a date of first use is determined for each substance used by a respondent. Estimates of the number of initiates, rates of initiation, and average age at first use can be constructed for specific time periods. For example, estimates for calendar years from 1965 to 2003 are tabulated, based on combined 2002-2004 NSDUH data, to show long-term trends in initiation.

Recent methodological assessments of long-term trend estimates based on calendar year of initiation have suggested that they are biased, due to suspected recall errors that seem to increase with the length of recall (Gfroerer et al., 2004). Evidence of telescoping, where respondents shift their reported age at first use either closer to their current age or further from the interview date, also has been found (Golub, Johnson, & Labouvie, 2000; Johnson & Schultz, in press). This report introduces a new approach for studying substance use initiation. Estimates discussed in this chapter describe initiation of substance use that occurred in the 12 months prior to the interview, and individuals who initiated use within the past 12 months are defined as recent initiates. Estimates for each year are produced independently based on the data from the survey conducted that year. This should improve the comparability of estimates across years, giving a more accurate assessment of recent trends. Although this approach will not eliminate reporting biases, it should minimize recall bias because the estimates are based on a more recent time period than the previously produced calendar year estimates. See Section B.4.4 in Appendix B of the full report for further discussion of methods and bias in initiation estimates.

Marijuana. In 2004, an estimated 2.1 million persons had used marijuana for the first time within the past 12 months—approximately 6,000 per day (Figure 6). This estimate was not significantly different from the number in 2003 (2.0 million), but there was a significant decline in the number of recent marijuana initiates between 2002 (2.2 million) and 2003 (2.0 million). Most (63.8 percent) of the 2.1 million recent marijuana initiates were younger than age 18 when they first used. Consistent with the decline in current marijuana use among male youths discussed in Chapter 2, the initiation rate (i.e., the percentage who initiated in the past year among those who had never used) for male youths declined from 6.3 percent in 2002 to 5.2 percent in 2003 and remained unchanged in 2004 (5.3 percent). Among female youths, there was no significant change in the incidence over the 3-year period (6.7, 6.2, and 6.3 percent, respectively).

 

Figure 6. Past Year Initiates for Illicit Drug Categories: 2004

Figure 6     D

Cocaine. In 2004, an estimated 1.0 million persons had used cocaine for the first time within the past 12 months—approximately 2,700 per day. This was not significantly different from the number in 2002 (1.0 million) or 2003 (1.0 million). Most (65.8 percent) of the 1.0 million recent cocaine initiates were aged 18 or older when they first used.

Heroin. In 2004, an estimated 118,000 persons had used heroin for the first time within the past 12 months. The average age of first use among recent initiates was 24.4 years in 2004. There were no significant changes in the number of initiates or in the average age of first use from 2002 to 2004 (Figure 7).

 

Figure 7. Mean Age for Past Year Initiates, by Illicit Drug: 2004

Figure 7     D

Hallucinogens. In 2004, an estimated 934,000 persons used hallucinogens for the first time within the past 12 months. This was not significantly different from the estimate in 2003 (886,000), but it was lower than the estimate in 2002 (1.2 million). Although there was little change between 2003 and 2004 in the number of past year initiates of LSD or Ecstasy, there were declines between 2002 and 2003. The number of past year LSD initiates was 338,000 in 2002, 200,000 in 2003, and 235,000 in 2004. Ecstasy initiation was 1.2 million in 2002, 642,000 in 2003, and 607,000 in 2004. Most (57.7 percent) of the recent Ecstasy initiates in 2004 were aged 18 or older at the time they first used Ecstasy.

Inhalants. In 2004, an estimated 857,000 persons had used inhalants for the first time within the past 12 months. Most (75.0 percent) recent initiates were under age 18 when they first used. There were no significant changes in the number of inhalant initiates from 2002 to 2004.

Psychotherapeutics. This category includes nonmedical use of any prescription-type pain reliever, tranquilizer, stimulant, or sedative. Over-the-counter substances are not included. In 2004, an estimated 2.8 million persons used psychotherapeutics nonmedically for the first time within the past year. The numbers of new users of psychotherapeutics in 2004 were 2.4 million for pain relievers, 1.2 million for tranquilizers, 793,000 for stimulants, and 240,000 for sedatives. These estimates are similar to the corresponding estimates for 2002 and 2003.

In 2004, the number of new nonmedical users of OxyContin® was 615,000, with an average age at first use of 24.5 years. Comparable data on past year OxyContin® initiation are not available for prior years, but calendar year estimates of OxyContin® initiation show a steady increase in the number of initiates from 1995, the year this drug was first available, through 2003 (Figure 8).

 

Figure 8. Annual Numbers of New Nonmedical Users of OxyContin®: 1995-2003

Figure 8     D

The number of recent new users of methamphetamine nonmedically was 318,000 in 2004. Between 2002 and 2004, the number of methamphetamine initiates remained level at around 300,000 per year. The average age of new users was 18.9 years in 2002, 20.4 years in 2003, and 22.1 years in 2004.

Alcohol. In 2004, an estimated 4.4 million persons had used alcohol for the first time within the past 12 months—approximately 12,000 per day. This was significantly greater than in 2002 (3.9 million) and 2003 (4.1 million). Most (86.9 percent) of the 4.4 million recent alcohol initiates were younger than 21 at the time of initiation. In 2004, the average age of first alcohol use among recent initiates was 17.5 years. This average age was 16.7 years in 2002 and 16.5 years in 2003, but these are not statistically different from the average age of first use in 2004. Excluding initiation occurring at age 21 or older, the mean ages were 15.5 years in 2002, 15.6 years in 2003, and 15.6 years in 2004.

Tobacco. The number of persons who smoked cigarettes for the first time within the past 12 months was 2.1 million in 2004, which was not significantly different from the estimates for 2002 (1.9 million) and 2003 (2.0 million). Most new smokers were under age 18 when they first smoked cigarettes (67.8 percent). In 2004, the number of persons who had started smoking cigarettes daily within the past 12 months was 1.1 million, or about 3,000 per day. This estimate is similar to the estimates for 2002 (1.0 million) and 2003 (1.1 million). An estimated 49.5 percent, or 0.5 million (about 1,500 per day), of these new daily smokers were younger than age 18 when they started smoking daily. In 2004, an estimated 3.1 million persons aged 12 or older used cigars for the first time in the past 12 months, a significant increase in the number of initiates from 2003 (2.7 million) but unchanged from 2002 (2.9 million). The number of persons initiating use of smokeless tobacco in the past year in 2004 was 999,000, similar to the numbers in 2002 and 2003.

 

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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 appear to reduce 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).

In this chapter, rates of substance use are compared for persons responding differently to questions reflecting risk or protective factors. However, associations discussed in this chapter should not be inferred to reflect causal connections. NSDUH data for an individual are collected at only one point in time, making it impossible to determine, for example, whether a lowering of perceived risk preceded the substance use or vice versa. It is also not possible to determine whether observed associations could be explained better by other factors not considered in the analysis or not measured in the survey.

Perceptions of Risk. One factor thought to 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. Response choices for these items were "great risk," "moderate risk," "slight risk," or "no risk."

Increases over time in the perceived risk of using a substance frequently are associated with concurrent or subsequent decreases in the rate of use of the substance and vice versa. For example, the proportion of youths who reported perceiving great risk from smoking one or more packs of cigarettes per day increased from 63.1 percent in 2002 to 67.5 percent in 2004 (Figure 9). Over the same period, the rate of past month cigarette use among youths decreased from 13.0 to 11.9 percent, and the rate of lifetime cigarette use declined from 33.3 to 29.2 percent.

 

Figure 9. Perceived Great Risk of Cigarette and Alcohol Use among Youths Aged 12 to 17: 2002-2004

Figure 9     D

The perceived risk of heavy alcohol use remained stable from 2002 to 2004 based on two measures (Figure 9). Declines were seen from 2003 to 2004 in the perceived risk of cocaine and heroin use (Figure 10).

 

Figure 10. Perceived Great Risk of Use of Selected Illicit Drugs among Youths Aged 12 to 17: 2002-2004

Figure 10     D

The perceived risk from smoking marijuana once a month increased from 32.4 percent in 2002 to 34.9 percent in 2003, then remained stable at 35.0 percent in 2004. The perception of great risk in smoking marijuana once or twice a week increased from 51.5 percent in 2002 to 54.4 percent in 2003, then remained stable at 54.7 percent in 2004 (Figure 10). From 2002 to 2004, there were declines in marijuana use in the lifetime (from 20.6 to 19.0 percent) and in the past year (from 15.8 to 14.5 percent).

Perceived Availability. Over half (52.2 percent) of youths aged 12 to 17 reported in 2004 that it would be "fairly easy" or "very easy" for them to obtain marijuana if they wanted some. One quarter reported it would be easy to get cocaine (24.4 percent) or crack (25.0 percent). One in seven (14.0 percent) indicated that heroin would be "fairly" or "very" easily available, and one in six (16.9 percent) said it would be easy for them to get LSD.

The perceived availability of marijuana decreased from 55.0 percent in 2002 to 53.6 percent in 2003 and to 52.2 percent in 2004. The perceived availability of crack declined from 26.2 percent in 2003 to 25.0 percent in 2004, and the proportion who reported that heroin would be easily available decreased from 15.3 to 14.0 percent. Perceived LSD availability declined from 19.4 percent in 2002 to 17.6 percent in 2003, then remained relatively stable between 2003 and 2004 (16.9 percent in 2004).

Perceived Parental Disapproval of Substance Use. In 2004, 90.6 percent of youths aged 12 to 17 reported that their parents would strongly disapprove of their smoking one or more packs of cigarettes per day, while the remaining 9.4 percent believed their parents would "somewhat disapprove" or "neither approve nor disapprove." A majority of youths (89.8 percent) reported that their parents would strongly disapprove of their trying marijuana or hashish once or twice, and 89.0 percent reported their parents would strongly disapprove of their having one or two drinks of an alcoholic beverage nearly every day. These rates of perceived parental disapproval in 2004 were similar to those seen in 2002 and 2003.

Youths who believed their parents would strongly disapprove of their using a particular substance were less likely to engage in use of that substance than were youths who believed their parents would somewhat disapprove or neither approve nor disapprove. For example, past month cigarette use was reported by 8.8 percent of youths who perceived strong parental disapproval of their smoking one or more packs of cigarettes per day compared with 42.2 percent of youths who believed their parents would not strongly disapprove. Current marijuana use also was much less prevalent among youths who perceived strong parental disapproval for trying marijuana or hashish once or twice than for those who did not (5.1 vs. 30.0 percent).

Fighting and Delinquent Behavior. In 2004, 23.1 percent of youths aged 12 to 17 reported that, in the past year, they had gotten into a serious fight at school or at work; 17.0 percent had taken part in a group-against-group fight; 3.3 percent had carried a handgun at least once; 3.8 percent had sold illegal drugs; 4.5 percent had, at least once, stolen or tried to steal something worth more than $50; and 8.2 percent had, in at least one instance, attacked others with intent to seriously hurt them. For all but one of these measures, the rate in 2004 was similar to that observed in 2003. The exception was the percentage of youths who had taken part in group-against-group fights, which increased from 15.9 percent in 2002 to 18.1 percent in 2003 then decreased to 17.0 percent in 2004.

Youths who had engaged in fighting or other delinquent behaviors were more likely than other youths to have used illicit drugs. For example, past month illicit drug use was reported by 18.9 percent of youths who had gotten into serious fights at school or work compared with 8.1 percent of those who had not and by 40.9 percent of those who had stolen or tried to steal something worth over $50 compared with 9.1 percent of those who had not.

Religious Beliefs and Participation in Activities. In 2004, 32.0 percent of youths aged 12 to 17 reported that they had attended religious services 25 or more times in the past year; 77.0 percent expressed agreement with the statement that religious beliefs are a very important part of their lives; 68.0 percent agreed with the statement that religious beliefs influence how they make decisions in life; and 34.1 percent agreed with the statement that it is important for their friends to share their religious beliefs. Findings for these measures remained stable from 2003 to 2004. Drug, alcohol, and cigarette use were lower among youths who agreed with these statements than among those who disagreed. For example, past month illicit drug use was reported by 8.1 percent of those who agreed that religious beliefs are a very important part of life compared with 18.5 percent of those who disagreed with that statement.

Exposure to Substance Use Prevention Messages and Programs. One in eight youths (12.2 percent) reported in 2004 that they had participated in drug, tobacco, or alcohol prevention programs outside of school in the past year. Participation in such programs increased from 12.7 percent of youths in 2002 to 13.9 percent in 2003, but then declined to 12.2 percent in 2004. The prevalence of alcohol use was generally lower among youths who reported participating in these programs than among youths who did not; for example, past month binge drinking was reported by 9.5 percent of youths who had participated in such programs compared with 11.3 percent of those who had not. However, rates of illicit drug use did not differ significantly between the two groups (e.g., past month marijuana use was reported by 7.9 percent of those who had participated in prevention programs outside of school and by 7.5 percent of those who had not participated in these types of programs).

In 2004, 60.3 percent of youths aged 12 to 17 reported that they had talked at least once in the past year with at least one of their parents about the dangers of drug, tobacco, or alcohol use; this rate represents an increase from 2003 (58.9 percent) and 2002 (58.1 percent). Among youths who reported having had such conversations with their parents, rates of current alcohol and cigarette use and past year and lifetime use of alcohol, cigarettes, and illicit drugs were lower than among youths who did not report such conversations. For example, past month binge drinking was reported by 10.5 percent of youths who had talked with their parents about drug, tobacco, or alcohol use compared with 12.0 percent of those who had not. Past month use of illicit drugs other than marijuana was reported by 4.6 percent of youths who had such conversations with their parents compared with 6.3 percent of those who had not. Almost four fifths (78.2 percent) of youths enrolled in school reported in 2004 they had seen or heard drug or alcohol prevention messages at school in the past year, a percentage similar to that observed in 2002 and 2003. Indicators of alcohol, cigarette, and illicit drug use were uniformly lower for youths exposed to such messages in school than for youths not reporting such exposure. Past month use of marijuana, for example, was reported by 7.1 percent of youths exposed to these messages at school compared with 10.6 percent of youths reporting no such exposure.

Out-of-school exposure to prevention messages in the past year was reported by 83.0 percent of youths aged 12 to 17 in 2004, a percentage similar to that in 2002 and 2003. Most indicators of current alcohol and drug use were similar for youths exposed to such out-of-school messages and those reporting no such exposure. However, past month use of illicit drugs was lower among those who were exposed than among those not exposed (10.3 vs. 11.8 percent).

 

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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 in the past 12 months. Substances include alcohol and illicit drugs, such as marijuana, cocaine, heroin, hallucinogens, and inhalants, and nonmedical use of prescription-type drugs. Respondents are classified 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 on dependence ask about health and emotional problems associated with substance use, unsuccessful attempts to cut down on use, tolerance, withdrawal, and other symptoms related to substance use. 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. The survey also asks about treatment for substance use problems. Specialty treatment is treatment received at drug or alcohol rehabilitation facilities, hospitals (inpatient only), or mental health centers. An individual is defined as needing treatment for a substance use problem he or she was dependent on or abused a substance or received specialty treatment in the past 12 months.

Dependence or Abuse, by Type of Substance. An estimated 22.5 million persons aged 12 or older in 2004 were classified with substance dependence or abuse in the past year (9.4 percent of the total population). Of these, 3.4 million were dependent on or abused both alcohol and illicit drugs, 3.9 million were dependent on or abused only illicit drugs, and 15.2 million were dependent on or abused only alcohol. Of the 7.3 million persons classified with dependence on or abuse of illicit drugs, 4.5 million were dependent on or abused marijuana, 1.6 million were dependent on or abused cocaine, and 1.4 million were dependent on or abused pain relievers. Between 2002 and 2004, there was no change in the number of persons with substance dependence or abuse (22.0 million in 2002, 21.6 million in 2003, and 22.5 million in 2004).

Dependence or Abuse, by Age. In 2004, the rate of substance dependence or abuse was 8.8 percent for youths aged 12 to 17, 21.2 percent for persons aged 18 to 25, and 7.3 percent for persons aged 26 or older. Among persons with substance dependence or abuse, 60.5 percent of youths aged 12 to 17, 39.2 percent of young adults aged 18 to 25, and 24.3 percent of adults aged 26 or older were dependent on or abused illicit drugs.

Dependence or Abuse, by Gender. In 2004, males aged 12 or older were twice as likely to be classified with substance dependence or abuse as females (12.7 vs. 6.2 percent) (Figure 11). Among youths aged 12 to 17, however, the rate of substance dependence or abuse among males (8.7 percent) was similar to the rate among females (9.0 percent).

 

Figure 11. Illicit Drug or Alcohol Dependence or Abuse, by Age and Gender: 2004

Figure 11     D

Dependence or Abuse, by Race/Ethnicity. Among persons aged 12 or older in 2004, the rate of substance dependence or abuse was highest among American Indians or Alaska Natives (20.2 percent). The next highest rates were among persons reporting two or more races (12.2 percent). Asians had the lowest rate (4.7 percent). The rates among Hispanics (9.8 percent) and whites (9.6 percent) were higher than the rate among blacks (8.3 percent).

Dependence or Abuse, by Employment Status. In 2004, an estimated 19.9 percent of unemployed adults aged 18 or older were classified with dependence or abuse, while 10.5 percent of full-time employed adults and 11.9 percent of part-time employed adults were classified as such. Most adults with substance dependence or abuse in 2004 were employed either full or part time. Of the 20.3 million adults classified with dependence or abuse, 15.7 million (77.6 percent) were employed.

Treatment, by Type of Substance. An estimated 3.8 million people aged 12 or older (1.6 percent of the population) received treatment for a problem related to the use of alcohol or illicit drugs in 2004. Of these, 1.5 million received treatment for the use of both alcohol and illicit drugs, 0.7 million received treatment for the use of illicit drugs but not alcohol, and 1.2 million received treatment for the use of alcohol but not illicit drugs.

Location of Treatment. Of the 3.8 million persons who received treatment for alcohol or illicit drug use in the past year, 2.3 million received treatment at a specialty substance use treatment facility, including 1.7 million at a rehabilitation facility as an outpatient, 947,000 at a rehabilitation facility as an inpatient, 775,000 at a hospital as an inpatient, and 982,000 at a mental health center as an outpatient. Non-specialty treatment locations were self-help groups (2.1 million persons), private doctor's offices (490,000), emergency rooms (453,000), and prisons or jails (310,000). (Note that persons could report receiving treatment at more than one location.)

Treatment Need, Specialty Treatment, and Perceived Need for Treatment. In 2004, the estimated number of persons aged 12 or older needing treatment for an alcohol or illicit drug use problem was 23.48 million (9.8 percent of the total population). An estimated 2.33 million of these people (1.0 percent of the total population and 9.9 percent of the people who needed treatment) received treatment at a specialty facility. Thus, there were 21.15 million persons (8.8 percent of the total population) who needed treatment but did not receive treatment at a specialty substance abuse facility in 2004.

The estimated number of persons needing but not receiving treatment for a substance use problem was slightly higher in 2004 (21.1 million) than in 2003 (20.3 million), but this difference was not statistically significant. The estimate of the number receiving specialty treatment in 2004 (2.3 million) was significantly higher than the estimate in 2003 (1.9 million), but it was essentially the same as the estimate in 2002 (2.3 million). The overall number needing treatment was higher in 2004 (23.5 million) than in 2003 (22.2 million).

Of the 21.1 million people who needed but did not receive treatment in 2004, an estimated 1.2 million (5.8 percent) reported that they felt they needed treatment for their alcohol or drug use problem (Figure 12). Of the 1.2 million persons who felt they needed treatment, 441,000 (35.8 percent) reported that they made an effort but were unable to get treatment, and 792,000 (64.2 percent) reported making no effort to get treatment.

 

Figure 12. Past Year Perceived Need and Effort Made to Receive Specialty Treatment among Persons Aged 12 or Older Needing But Not Receiving Treatment for Illicit Drugs or Alcohol Use: 2004

Figure 12     D

The number of people who felt they needed treatment and made an effort to get it among those who needed but did not receive treatment was higher in 2004 (441,000) than in 2003 (273,000), but it was similar to the number in 2002 (446,000).

Based on 2003-2004 combined data, the most often reported reasons for not receiving illicit drug or alcohol use treatment among persons who needed but did not receive treatment and felt they needed treatment were not ready to stop using (40.0 percent), cost or insurance barriers (34.5 percent), stigma (21.6 percent), and did not feel the need for treatment (at the time) or could handle the problem without treatment (13.9 percent). Among the people who made an effort to get treatment, the most often reported reasons for not receiving treatment were cost or insurance barriers (42.5 percent), not ready to stop using (25.3 percent), other access barriers (21.5 percent), and stigma (17.8 percent) (Figure 13).

 

Figure 13. Reasons for Not Receiving 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: 2003-2004 Combined

Figure 13     D

Illicit Drug Use Treatment Need. Between 2003 and 2004, the number of persons needing treatment increased from 7.3 million to 8.1 million, and the number receiving specialty treatment increased from 1.1 million to 1.4 million. These 2004 estimates were similar to the corresponding estimates in 2002 (7.7 million needing treatment, 1.4 million receiving treatment).

Of the 6.6 million people who needed but did not receive specialty treatment for illicit drug use in 2004, an estimated 598,000 (9.0 percent) reported that they felt they needed treatment for their illicit drug use problem. This number increased from 362,000 in 2002 and 426,000 in 2003. Of the 598,000 persons who felt they needed treatment in 2004, 194,000 (32.4 percent) reported that they made an effort but were unable to get treatment, and 404,000 (67.6 percent) reported making no effort to get treatment.

 

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8. Prevalence and Treatment of Mental Health Problems

The National Survey on Drug Use and Health (NSDUH) collects information on several aspects of mental health in the United States, including the prevalence and treatment of serious psychological distress (SPD) and major depressive episodes (MDE) and the association of these problems with substance use. Past year SPD is an overall indicator of nonspecific psychological distress that is constructed from the K6 scale administered to adults aged 18 or older in the survey. The K6 scale consists of six questions that gather information on how frequently a respondent experienced symptoms of psychological distress during the 1 month in the past year when he or she was at his or her worst emotionally. Responses to these six questions are combined to produce a score ranging from 0 to 24, where a score of 13 or greater is considered SPD. This cutoff is based on research suggesting that scores above this threshold provide an indicator of serious mental illness. Although previous reports from the Substance Abuse and Mental Health Services Administration (SAMHSA) have referred to this measure as "serious mental illness (SMI)" and research has shown that the measure is highly correlated with measures of SMI, SAMHSA has determined that it is appropriate to report these estimates (for 2002, 2003, and 2004) as the prevalence of SPD, not SMI. See Section B.4.4 in Appendix B of the full report for further discussion.

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 symptoms that met the criteria for major depressive disorder as described in the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (American Psychiatric Association [APA], 1994). It should be noted that no exclusions were made for MDE caused by medical illness, bereavement, or substance use disorders.

Although there is significant overlap between those meeting the criteria of SPD and MDE, there are important distinctions between the two. Meeting the criteria for SPD indicates that the respondent exhibited a high level of distress due to any type of mental problem, which may include general symptoms related to phobia, anxiety, or depression. However, meeting the criteria for MDE indicates that the respondent had the specific physical and emotional symptom profile indicative of major depression.

It is important to note that because the sample frame of the survey includes only the U.S. civilian, noninstitutionalized population, persons who were residing in long-term psychiatric or other institutions at the time of interview were excluded from the NSDUH sample.

Prevalence of Serious Psychological Distress. In 2004, there were an estimated 21.4 million adults aged 18 or older with SPD. This represents 9.9 percent of all adults, similar to the rate of 9.2 percent in 2003 but higher than the rate of 8.3 percent in 2002 (Figure 14). Rates of SPD in 2004 were highest for adults aged 18 to 25 (13.7 percent) and lowest for those aged 50 or older (7.9 percent). The prevalence of SPD among women (12.0 percent) was higher than that among men (7.7 percent).

 

Figure 14. Rates of Serious Psychological Distress in the Past Year among Adults Aged 18 or Older, by Age: 2002-2004

Figure 14     D

Serious Psychological Distress and Substance Use. Among adults with SPD, 27.6 percent used an illicit drug in the past year compared with 11.8 percent among those without SPD. Similarly, the rate of past month cigarette use was 40.8 percent among adults with SPD, and 24.5 percent among adults without SPD.

SPD was not strongly linked with past year or current alcohol use, but there was an association between SPD and binge and heavy alcohol use. The rate of current alcohol use in 2004 among adults with SPD was similar to the rate among those without SPD (52.1 vs. 53.3 percent). However, the rate of heavy alcohol use in the past month among adults with SPD was higher (9.7 percent) than among adults without SPD (7.0 percent).

Serious Psychological Distress and Substance Dependence or Abuse. SPD was highly correlated with substance dependence or abuse. Among adults with SPD in 2004, 21.3 percent (4.6 million) were dependent on or abused illicit drugs or alcohol. The rate among adults without SPD was 7.9 percent.

Treatment among Adults with Serious Psychological Distress. Among the 21.4 million adults with SPD in 2004, 10.3 million (48.1 percent) received treatment for a mental health problem in the past year. This is similar to the estimates in 2002 (47.9 percent) and 2003 (47.2 percent). Among adults with SPD in the past year who did not receive treatment and reported an unmet need for treatment, cost or insurance issues were the most frequently reported reason for not obtaining treatment (57.6 percent). Other reasons for not receiving treatment identified by these respondents included not feeling a need for treatment at the time or believing that the problem could be handled without treatment (32.1 percent), stigma associated with treatment (28.6 percent), not knowing where to go for services (25.9 percent), and not having time (12.9 percent).

Treatment among Adults with Co-Occurring Serious Psychological Distress and Substance Use Disorders. Among the 4.6 million adults with SPD and a substance use disorder in 2004, 47.5 percent (about 2.2 million) received treatment for mental health problems, and 11.0 percent (503,000 adults) received specialty substance use treatment (Figure 15). About half (47.5 percent) of adults with both SPD and a substance use disorder received no treatment for either problem. Only 6.0 percent (274,000 adults) received both treatment for mental health problems and specialty substance use treatment. Another 41.4 percent received only treatment for mental health problems, and 5.0 percent received only specialty substance use treatment.

 

Figure 15. Past Year Treatment among Adults Aged 18 or Older with Both Serious Psychological Distress and a Substance Use Disorder: 2004

Figure 15     D

Prevalence of Major Depressive Episodes. In 2004, an estimated 35.1 million persons (14.7 percent of the population) aged 12 or older had at least one MDE in their lifetime, and 19.3 million persons (8.1 percent of the population) had at least one MDE in the past year. In 2004, an estimated 2.2 million youths aged 12 to 17 and 17.1 million adults aged 18 or older had at least one MDE during the past year. The lifetime prevalence of MDE was 14.0 percent among persons aged 12 to 17, 16.6 percent among persons aged 18 to 25, and 14.5 percent among persons aged 26 or older. The past year prevalence of MDE was highest for adults aged 18 to 25 (10.1 percent) and lowest for those aged 26 or older (7.6 percent). The rate among youths aged 12 to 17 was 9.0 percent. The past year prevalence of MDE was higher among females than among males (10.6 vs. 5.5 percent). Rates of lifetime and past year MDE were higher for females than males in all age groups.

Major Depressive Episodes and Substance Use. In 2004, persons with MDE in the past year were more likely than those without MDE to have used an illicit drug in the past year. Among persons with an MDE, 28.8 percent used an illicit drug in the past year, while among those without an MDE only 13.8 percent used an illicit drug. A similar pattern was observed for specific types of past year illicit drug use, such as marijuana, cocaine, heroin, hallucinogens, inhalants, and the nonmedical use of psychotherapeutics. Past month heavy alcohol use, defined as drinking five or more drinks on 5 or more days in the past 30 days, also was associated with an MDE in the past year. Among persons with an MDE, 9.2 percent were heavy alcohol users compared with 6.9 percent of persons without an MDE. Similarly, among persons with an MDE, the rate of daily cigarette use was 25.5 percent, while the rate was 15.1 percent among persons without an MDE.

Co-Occurrence of Major Depressive Episodes with Substance Dependence or Abuse. Having MDE in the past year also was associated with substance dependence or abuse. Among persons aged 12 or older with MDE in 2004, 22.0 percent were dependent on or abused alcohol or illicit drugs, while among persons without MDE 8.6 percent were dependent on or abused alcohol or illicit drugs. Persons with MDE were more likely than those without MDE to be dependent on or abuse illicit drugs (9.6 vs. 2.7 percent) and alcohol (16.8 vs. 7.1 percent). Among persons with substance dependence or abuse, 18.5 percent had at least one MDE in the past year compared with 7.0 percent among those who did not have substance dependence or abuse.

Treatment for Major Depressive Episodes. Among persons aged 12 or older who had MDE in the past year, 62.3 percent received treatment (i.e., saw or talked to a medical doctor or other professional or used prescription medication) for depression within the same time period.

Among adults 18 or older with MDE in the past year, less than half of those with no insurance (41.1 percent) received treatment for depression in the past year compared with 70.3 percent of adults with private insurance, 74.3 percent of adults with Medicaid or CHIP, and 82.6 percent of adults with other health insurance, including Medicare, CHAMPUS, TRICARE, CHAMPVA, VA, and other sources of health care or insurance.

There were differences by age group in the type of professional seen among persons with MDE in the past year who saw or talked to a professional in the past year about depression. Adults aged 18 years or older were more likely than youths aged 12 to 17 to see a family doctor (58.7 vs. 25.5 percent) or other medical doctors (11.3 vs. 5.0 percent) about depression in the past year. In contrast, youths were more likely than adults to see psychologists (32.2 vs. 26.0 percent) or counselors (58.2 vs. 20.7 percent).

Role Impairment Resulting from Major Depressive Episodes. An estimated 1.5 million youths aged 12 to 17 years old with MDE in the past year experienced severe to very severe impairment in at least one of four role domains (home, school/work, close relationships, social life) due to depression. This represents 69.2 percent of youths with MDE and 6.1 percent of all youths. An estimated 11.2 million adults with MDE in the past year experienced severe or very severe impairment in at least one of these four role domains due to depression (66.3 percent of adults with MDE, 5.2 percent of all adults). An estimated 5.5 million adults with MDE in the past year reported severe or very severe impairment in their ability to carry out work activities in the past year as the result of their depression (Figure 16).

 

Figure 16. Percentage with Severe or Very Severe Role Impairment as Measured by the Sheehan Disability Scale (SDS) among Persons Aged 12 or Older with a Major Depressive Episode in the Past Year: 2004

Figure 16     D

Treatment and Unmet Treatment Need among Adults. In 2004, an estimated 27.5 million adults received treatment for mental health problems during the past 12 months. This represents 12.8 percent of the population 18 years or older and is similar to the rate in 2002 and 2003. The treatment type most often reported by the adult population in 2004 was prescription medication (10.5 percent), followed by outpatient treatment (7.1 percent). About 1.9 million adults (0.9 percent) received inpatient care for mental health problems during the past year. These patterns of utilization were not significantly different from those seen in 2002 and 2003, although the rate of inpatient treatment was higher in 2004 than in 2002 (0.7 percent).

Similar to 2002 and 2003, more than half of adults who received treatment or counseling for mental health problems in 2004 (54.7 percent) reported that the treatment improved their ability to manage daily activities "a great deal or a lot." In 2004, 10.9 million adults (5.1 percent) reported an unmet need for treatment or counseling for mental health problems in the past year. This includes 5.6 million adults who did not receive treatment. Among adults who did receive treatment or counseling for a mental health problem in the past year, 19.1 percent reported an unmet need. This may reflect a delay in treatment or receipt of insufficient treatment. Among the 5.6 million adults who reported an unmet need and did not receive treatment in the past year, several barriers to treatment were reported. These included cost or insurance issues (47.2 percent), not feeling a need for treatment at the time or believing that the problem could be handled without treatment (37.6 percent), stigma associated with treatment (25.8 percent), and not knowing where to go for services (19.9 percent).

Treatment for Mental Health Problems among Youths. In 2004, 5.7 million youths aged 12 to 17 (22.5 percent) received treatment or counseling for emotional or behavior problems in the year prior to the interview. This is higher than the estimates for 2002 (19.3 percent) and 2003 (20.6 percent).

 

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9. Discussion of Trends in Substance Use Prevalence

This report presents findings from the 2004 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, 2003, and 2004 estimates are not comparable with estimates from 2001 and earlier surveys. The primary focus of the report is on comparisons across subgroups of the U.S. population in 2004 and changes between 2003 and 2004, as well as between 2002 and 2004, in the substance use and mental health measures addressed by the survey. Some of the key findings for 2004 are presented in the Highlights section of this report (Section 1.4). This chapter provides an additional discussion of the findings concerning a topic of great interest—trends in substance use among youths and young adults.

The 2002-2004 NSDUHs show that among youths aged 12 to 17, the use of alcohol, inhalants, cocaine, and pain relievers used nonmedically did not change significantly, while cigarette use declined. Youth marijuana use also declined, but slowly, and primarily among males, and not in the West region. However, data on marijuana incidence suggest that the recent declining trend in marijuana prevalence may not continue in 2005. The percentage of youths who used marijuana for the first time within the past 12 months was 4.9 percent in 2003 and 5.0 percent in 2004. Among young adults aged 18 to 25, trends were similar to the trends for youths, except that there was no decline in cigarette use in this age group. The past month cigarette smoking rate among young adults remained at about 40 percent in 2004.

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 provide confirmation or support for 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 E of the full report, along with descriptions of methods and results from other substance use and mental health data sources.

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 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 earlier participated in the study as 12th graders (2004 data from the adult survey are not available at this time) (Johnston, O'Malley, Bachman, & Schulenberg, 2005). Historically, NSDUH rates of substance use among youths have been lower than those of MTF, but the two sources have usually shown similar trends.

Recent Trends in Substance Use

A comparison of NSDUH and MTF estimates for 2002, 2003, and 2004 is shown in Table s 1 and 2 for several substances that are defined similarly in the two surveys. MTF data on 8th and 10th graders combined give the closest match on age to NSDUH youth estimates, while MTF follow-up data on persons aged 19 to 24 provide the closest match on age to NSDUH young adult estimates. The NSDUH results are very consistent with MTF trends. Both surveys show decreases among youths and young adults for some measures of use of illicit drugs, alcohol, and cigarettes between 2002 and 2004, although not all decreases are statistically significant. The gender difference in the youth marijuana use trend described in Chapter 2 of this report also is evident in MTF data. The rate of past year marijuana use among male 8th and 10th graders dropped from 24.7 percent in 2002 to 20.7 percent in 2004, while among females in these grades the rate was 20.4 percent in 2002 and 18.5 percent in 2004 (Johnston, O'Malley, Bachman, & Schulenberg, in press).

Long-Term Trends in the Use of Marijuana, Cocaine, and Nonmedical Psychotherapeutics

In this section, trends in the use of two illicit drugs of concern, marijuana and cocaine, are described along with trends in the nonmedical use of prescription-type psychotherapeutics. Methodology changes throughout NSDUH's history make it difficult to assess long-term trends. However, it is instructive to compare NSDUH estimates from 1971 to 2004 by "piecing together" the data from time periods for which data are comparable. Specifically, valid trend comparisons can be made for 1971-1998, 1999-2001, and 2002-2004. With this approach, comparisons between 1998 and 1999, and between 2001 and 2002, are made with caution because they are potentially biased due to methods changes. Nevertheless, when these data are combined in a single presentation, it often becomes clear that the effects of the methods changes are small compared with the major shifts in substance use prevalence that have occurred over the past three decades. For example, NSDUH data show an increase in youth and young adult marijuana use in the 1970s, followed by a decrease in the 1980s and another less pronounced increase among youths in the early 1990s (Figures 17 and 18). These trends also are evident in MTF data, as well as in NSDUH retrospectively reported incidence data presented in Figure 5.1 in Chapter 5 of the full report.

 

Figure 17. Past Month Marijuana Use among Youths Aged 12 to 17: 1971-2004

Figure 17     D

 

Figure 18. Past Month Marijuana Use among Persons Aged 18 to 25: 1971-2004

Figure 18     D

The trend in cocaine use during the 1970s and 1980s shows a similar pattern to that of marijuana, although cocaine use lagged by several years and occurred among an older group of users (Figure 19). These results are consistent with MTF data (not shown). Marijuana use increased in the early 1970s, until it peaked in 1979, while cocaine use did not dramatically increase until the late 1970s, peaking in 1982 among youths, in 1979 among young adults aged 18 to 25, and in 1985 among persons aged 26 to 34. Marijuana use peaked in 1979 for all three of these age groups (data for those aged 26 to 34 are not shown; see Table 7.128B in the 2004 Detailed Tables). These trends for marijuana and cocaine are consistent with prior studies that have shown that more than 90 percent of cocaine users during the early 1980s had used marijuana prior to initiating cocaine use (Adams, Rouse, & Gfroerer, 1990); the same appears to be true for cocaine users in 2004.

 

Figure 19. Past Year Cocaine Use among Persons Aged 12 or Older, by Age: 1972-2004

Figure 19     D

Trend data for nonmedical use of prescription-type psychotherapeutics among persons aged 12 or older showed a decrease from 1985 to 1990, followed by a gradual decline; the rate was lower in 1998 than in 1991. Methodological changes limit inferences about trends between 1998 and 1999 and from 2001 to 2002. A significant 1-year increase occurred from 2000 to 2001, but from 2002 to 2004 the rate remained stable (Figure 20).

 

Figure 20. Past Year Nonmedical Prescription-Type Psychotherapeutic Use among Persons Aged 12 or Older: 1985-2004

Figure 20     D

 

Table 1. Comparison of NSDUH and MTF Prevalence Rates among Youths: 2002-2004

  NSDUH MTF
Age 12-17 8th and 10th Grades
2002 2003 2004 2002 2003 2004
Marijuana            
     Lifetime 20.6a,b 19.6   19.0   29.0a,b 27.0   25.7  
     Past Year 15.8b   15.0   14.5   22.5a,b 20.5   19.7  
     Past Month 8.2     7.9   7.6   13.1b   12.3b 11.2  
Cocaine            
     Lifetime 2.7     2.6   2.4   4.9     4.4   4.4  
     Past Year 2.1b   1.8   1.6   3.2     2.8   2.9  
     Past Month 0.6     0.6   0.5   1.4     1.1   1.3  
Ecstasy            
     Lifetime 3.3a,b 2.4   2.1   5.5a,b 4.3b 3.6  
     Past Year 2.2a,b 1.3   1.2   3.9a,b 2.6b 2.1  
     Past Month 0.5b   0.4   0.3   1.6a,b 0.9   0.8  
LSD            
     Lifetime 2.7a,b 1.6b 1.2   3.8a,b 2.8   2.3  
     Past Year 1.3a,b 0.6   0.6   2.1a,b 1.5   1.4  
     Past Month 0.2     0.2   0.2   0.7     0.6   0.6  
Inhalants            
     Lifetime 10.5     10.7   11.0   14.4     14.3   14.9  
     Past Year 4.4     4.5   4.6   6.8b   7.1b 7.8  
     Past Month 1.2     1.3   1.2   3.1     3.2   3.5  
Alcohol            
     Lifetime 43.4b   42.9   42.0   57.0b   55.8b 54.1  
     Past Year 34.6     34.3   33.9   49.4b   48.3   47.5  
     Past Month 17.6     17.7   17.6   27.5     27.6   26.9  
Cigarettes            
     Lifetime 33.3a,b 31.0b 29.2   39.4a,b 35.7   34.3  
     Past Year 20.3a,b 19.0   18.4   --     --   --  
     Past Month 13.0b   12.2   11.9   14.2b   13.5   12.6  

 

Table 2. Comparison of NSDUH and MTF Prevalence Rates among Young Adults: 2002-2004
  NSDUH MTF
Age 18-25 Age 19-24
2002 2003 2004 2002 2003 2004
Marijuana            
     Lifetime 53.8     53.9   52.8   56.1   56.4   --  
     Past Year 29.8a,b 28.5   27.8   34.2   33.0   --  
     Past Month 17.3b   17.0   16.1   19.8   19.9   --  
Cocaine            
     Lifetime 15.4     15.0   15.2   12.9   14.5   --  
     Past Year 6.7     6.6   6.6   6.5   7.3   --  
     Past Month 2.0     2.2   2.1   2.5   2.6   --  
Ecstasy            
     Lifetime 15.1b   14.8b 13.8   16.0   16.6   --  
     Past Year 5.8a,b 3.7b 3.1   8.0   5.3   --  
     Past Month 1.1a,b 0.7   0.7   1.6   1.0   --  
LSD            
     Lifetime 15.9a,b 14.0b 12.1   13.9   13.8   --  
     Past Year 1.8a,b 1.1   1.0   2.4   1.5   --  
     Past Month 0.1b   0.2   0.3   0.4   0.2   --  
Inhalants            
     Lifetime 15.7b   14.9   14.0   11.7   11.4   --  
     Past Year 2.2     2.1   2.1   2.2   1.5   --  
     Past Month 0.5     0.4   0.4   0.8   0.3   --  
Alcohol            
     Lifetime 86.7     87.1   86.2   88.4   87.6   --  
     Past Year 77.9     78.1   78.0   83.9   82.3   --  
     Past Month 60.5     61.4   60.5   67.7   66.3   --  
Cigarettes            
     Lifetime 71.2b   70.2b 68.7   --   --   --  
     Past Year 49.0a,b 47.6   47.5   41.8   40.8   --  
     Past Month 40.8     40.2   39.5   31.4   29.5   --  

 

References

Adams, E. H., Rouse, B. A., & Gfroerer, J. C. (1990). Populations at risk for cocaine use and subsequent consequences. In N. D. Volkow & A. C. Swann (Eds.), Cocaine in the brain (pp. 25-41). New Brunswick, NJ: Rutgers University Press.

American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (DSM-IV) (4th ed.). Washington, DC: Author.

Gfroerer, J., Hughes, A., Chromy, J., Heller, D., & Packer, L. (2004, July). Estimating trends in substance use based on reports of prior use in a cross-sectional survey. In S. B. Cohen & J. M. Lepkowski (Eds.), Eighth Conference on Health Survey Research Methods: Conference proceedings [Peachtree City, GA] (DHHS Publication No. PHS 04-1013, pp. 29-34). Hyattsville, MD: National Center for Health Statistics. [Available as a PDF at http://www.cdc.gov/nchs/data/misc/proceedings_hsrm2004.pdf]

Golub, A., Johnson, B. D., & Labouvie, E. (2000). On correcting bias in self-reports of age at first substance use with repeated cross-section analysis. Journal of Quantitative Criminology, 16(1), 45-68.

Hawkins, J. D., Catalano, R. F., & Miller, J. Y. (1992). Risk and protective factors for alcohol and other drug problems in adolescence and early adulthood: Implications for substance abuse prevention. Psychological Bulletin, 112(1), 64-105.

Johnson, E. O., & Schultz, L. (in press). Forward telescoping bias in reported age of onset: An example from cigarette smoking. International Journal of Methods in Psychiatric Research.

Johnston, L. D., O'Malley, P. M., & Bachman, J. G. (2003). Monitoring the Future national survey results on drug use, 1975-2002: College students and adults ages 19-40 (NIH Publication No. 03-5376, Vol. II). Bethesda, MD: National Institute on Drug Abuse. [Available as a PDF at http://www.monitoringthefuture.org/pubs.html]

Johnston, L. D., O'Malley, P. M., Bachman, J. G. , & Schulenberg, J. E. (2004a). Monitoring the Future national survey results on drug use, 1975-2003: College students and adults ages 19-45 (NIH Publication No. 04-5508, Vol. II). Bethesda, MD: National Institute on Drug Abuse. [Available as a PDF at http://www.monitoringthefuture.org/pubs.html]

Johnston, L. D., O'Malley, P. M., Bachman, J. G. , & Schulenberg, J. E. (2004b). Monitoring the Future national survey results on drug use, 1975-2003: Secondary school students (NIH Publication No. 04-5507, Vol. I). Bethesda, MD: National Institute on Drug Abuse. [Available as a PDF at http://monitoringthefuture.org/pubs.html]

Johnston, L. D., O'Malley, P. M., Bachman, J. G. , & Schulenberg, J. E. (in press). Monitoring the Future national survey results on drug use, 1975-2004: Secondary school students (NIH Publication No. 05-xxxx, Vol. I). Bethesda, MD: National Institute on Drug Abuse. [To be available as a PDF at http://monitoringthefuture.org/pubs.html]

Johnston, L. D., O'Malley, P. M., Bachman, J. G. , & Schulenberg, J. E. (2005). Monitoring the Future national results on adolescent drug use: Overview of key findings, 2004 (NIH Publication No. 05-5726). Bethesda, MD: National Institute on Drug Abuse. [Available at http://www.monitoringthefuture.org/pubs.html]

Office of Applied Studies, Substance Abuse and Mental Health Services Administration. (2005). Results from the 2004 National Survey on Drug Use and Health: National findings (DHHS Publication No. SMA 05-4062, NSDUH Series H-28). Rockville, MD: Substance Abuse and Mental Health Services Administration, Office of Applied Studies. [Available at http://www.oas.samhsa.gov/p0000016.htm#2k4]

Substance Abuse and Mental Health Data Archive. (2005). National Survey on Drug Use and Health (NSDUH) series. Retrieved June 12, 2005, from http://webapp.icpsr.umich.edu/cocoon/SAMHDA-SERIES/00064.xml

 

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Appendix: Prevalence Estimate Tables

50803 (1.1A REV)

Table A.1 Types of Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 12 or Older: Numbers in Thousands, 2002-2004
Drug TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 108,255  110,205  110,057  35,132  34,993  34,807  19,522  19,470  19,071 
     Marijuana and Hashish 94,946  96,611  96,772  25,755  25,231  25,451  14,584  14,638  14,576 
     Cocaine 33,910  34,891  34,153  5,902  5,908  5,658  2,020  2,281  2,021 
          Crack 8,402  7,949  7,840  1,554  1,406  1,304  567  604  467 
     Heroin 3,668  3,744a 3,145  404  314  398  166  119  166 
     Hallucinogens 34,314  34,363  34,333  4,749b 3,936  3,878  1,196b 1,042  929 
          LSD 24,516  24,424  23,398  999b 558  592  112  133  141 
          PCP 7,418  7,107  6,762  235  219  210  58  56  49 
          Ecstasy 10,150a 10,904  11,130  3,167b 2,119  1,915  676b 470  450 
     Inhalants 22,870  22,995  22,798  2,084  2,075  2,255  635  570  638 
     Nonmedical Use of Psychotherapeutics2 46,558  47,882  48,013  14,680  14,986  14,643  6,210  6,336  6,007 
          Pain Relievers 29,611a 31,207  31,768  10,992  11,671  11,256  4,377  4,693  4,404 
               OxyContin® 1,924b 2,832  3,072  --  --  1,213  --  --  325 
          Tranquilizers 19,267  20,220  19,852  4,849  5,051  5,068  1,804  1,830  1,616 
          Stimulants 21,072  20,798  19,982  3,181  2,751  2,918  1,218  1,191  1,189 
               Methamphetamine 12,383  12,303  11,726  1,541  1,315  1,440  597  607  583 
          Sedatives 9,960  9,510  9,891  981  831  737  436a 294  265 
ILLICIT DRUG OTHER THAN MARIJUANA1 70,300  71,128  70,657  20,423  20,305  19,658  8,777  8,849  8,247 

50803 (1.1B REV)

 

Table A.2 Types of Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 12 or Older: Percentages, 2002-2004

Drug TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 46.0  46.4  45.8  14.9  14.7  14.5  8.3  8.2  7.9 
     Marijuana and Hashish 40.4  40.6  40.2  11.0  10.6  10.6  6.2  6.2  6.1 
     Cocaine 14.4  14.7  14.2  2.5  2.5  2.4  0.9  1.0  0.8 
          Crack 3.6  3.3  3.3  0.7  0.6  0.5  0.2  0.3  0.2 
     Heroin 1.6a 1.6a 1.3  0.2  0.1  0.2  0.1  0.1  0.1 
     Hallucinogens 14.6  14.5  14.3  2.0b 1.7  1.6  0.5b 0.4  0.4 
          LSD 10.4a 10.3  9.7  0.4b 0.2  0.2  0.0  0.1  0.1 
          PCP 3.2a 3.0  2.8  0.1  0.1  0.1  0.0  0.0  0.0 
          Ecstasy 4.3  4.6  4.6  1.3b 0.9  0.8  0.3b 0.2  0.2 
     Inhalants 9.7  9.7  9.5  0.9  0.9  0.9  0.3  0.2  0.3 
     Nonmedical Use of Psychotherapeutics2 19.8  20.1  20.0  6.2  6.3  6.1  2.6  2.7  2.5 
          Pain Relievers 12.6  13.1  13.2  4.7  4.9  4.7  1.9  2.0  1.8 
               OxyContin® 0.8b 1.2  1.3  --  --  0.5  --  --  0.1 
          Tranquilizers 8.2  8.5  8.3  2.1  2.1  2.1  0.8  0.8  0.7 
          Stimulants 9.0a 8.8  8.3  1.4  1.2  1.2  0.5  0.5  0.5 
               Methamphetamine 5.3  5.2  4.9  0.7  0.6  0.6  0.3  0.3  0.2 
          Sedatives 4.2  4.0  4.1  0.4  0.3  0.3  0.2a 0.1  0.1 
ILLICIT DRUG OTHER THAN MARIJUANA1 29.9  29.9  29.4  8.7a 8.5  8.2  3.7a 3.7  3.4 

50803 (1.2B REV)

 

Table A.3 Types of Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 12 to 17: Percentages, 2002-2004

Drug TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 30.9  30.5  30.0  22.2a 21.8  21.0  11.6a 11.2  10.6 
     Marijuana and Hashish 20.6b 19.6  19.0  15.8b 15.0  14.5  8.2  7.9  7.6 
     Cocaine 2.7  2.6  2.4  2.1b 1.8  1.6  0.6  0.6  0.5 
          Crack 0.7  0.6  0.5  0.4a 0.4a 0.3  0.1  0.1  0.1 
     Heroin 0.4  0.3  0.3  0.2  0.1  0.2  0.0  0.1  0.1 
     Hallucinogens 5.7b 5.0  4.6  3.8b 3.1  3.0  1.0  1.0  0.8 
          LSD 2.7b 1.6a 1.2  1.3b 0.6  0.6  0.2  0.2  0.2 
          PCP 0.9a 0.8  0.7  0.4a 0.4  0.3  0.1  0.1  0.0 
          Ecstasy 3.3b 2.4  2.1  2.2b 1.3  1.2  0.5a 0.4  0.3 
     Inhalants 10.5  10.7  11.0  4.4  4.5  4.6  1.2  1.3  1.2 
     Nonmedical Use of Psychotherapeutics2 13.7  13.4  13.5  9.2  9.2  8.8  4.0  4.0  3.6 
          Pain Relievers 11.2  11.2  11.4  7.6  7.7  7.4  3.2  3.2  3.0 
               OxyContin® 0.9a 1.0  1.2  --  --  0.8  --  --  0.3 
          Tranquilizers 3.4  3.5  3.2  2.3  2.3  2.1  0.8  0.9a 0.6 
          Stimulants 4.3b 4.0b 3.4  2.6b 2.3  2.0  0.8  0.9  0.7 
               Methamphetamine 1.5a 1.3  1.2  0.9a 0.7  0.6  0.3  0.3  0.2 
          Sedatives 1.0  1.0  1.0  0.6  0.5  0.5  0.2a 0.2  0.1 
ILLICIT DRUG OTHER THAN MARIJUANA1 21.4  21.3  21.2  13.5  13.4  13.0  5.7  5.7  5.3 

50803 (1.3B REV)

 

Table A.4 Types of Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 18 to 25: Percentages, 2002-2004

Drug TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 59.8  60.5  59.2  35.5a 34.6  33.9  20.2  20.3  19.4 
     Marijuana and Hashish 53.8  53.9  52.8  29.8b 28.5  27.8  17.3a 17.0  16.1 
     Cocaine 15.4  15.0  15.2  6.7  6.6  6.6  2.0  2.2  2.1 
          Crack 3.8  3.8  3.5  0.9  0.9  0.8  0.2  0.2  0.3 
     Heroin 1.6  1.6  1.6  0.4  0.3  0.4  0.1  0.1  0.1 
     Hallucinogens 24.2b 23.3b 21.3  8.4b 6.7  6.0  1.9a 1.7  1.5 
          LSD 15.9b 14.0b 12.1  1.8b 1.1  1.0  0.1b 0.2  0.3 
          PCP 2.7a 3.0b 2.3  0.3  0.4  0.3  0.0  0.1  0.1 
          Ecstasy 15.1a 14.8a 13.8  5.8b 3.7a 3.1  1.1b 0.7  0.7 
     Inhalants 15.7b 14.9  14.0  2.2  2.1  2.1  0.5  0.4  0.4 
     Nonmedical Use of Psychotherapeutics2 27.7a 29.0  29.2  14.2  14.5  14.8  5.4a 6.0  6.1 
          Pain Relievers 22.1b 23.7  24.3  11.4  12.0  11.9  4.1a 4.7  4.7 
               OxyContin® 2.6b 3.6b 4.3  --  --  1.7  --  --  0.4 
          Tranquilizers 11.2a 12.3  12.2  4.9  5.3  5.2  1.6  1.7  1.8 
          Stimulants 10.8  10.8  10.6  3.7  3.5  3.7  1.2  1.3  1.4 
               Methamphetamine 5.7  5.2  5.2  1.7  1.6  1.6  0.5  0.6  0.6 
          Sedatives 2.1  1.8  1.9  0.5  0.5  0.5  0.2  0.2  0.2 
ILLICIT DRUG OTHER THAN MARIJUANA1 40.1  40.2  39.2  20.2  19.7  19.3  7.9  8.4  8.1 

50803 (1.4B REV)

 

Table A.5 Types of Illicit Drug Use in Lifetime, Past Year, and Past Month among Persons Aged 26 or Older: Percentages, 2002-2004

Drug TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 45.7  46.1  45.6  10.4  10.3  10.2  5.8  5.6  5.5 
     Marijuana and Hashish 40.8  41.2  41.0  7.0  6.9  7.0  4.0  4.0  4.1 
     Cocaine 15.9  16.3  15.6  1.8  1.9  1.7  0.7  0.8  0.7 
          Crack 3.9  3.6  3.6  0.7  0.6  0.5  0.3  0.3  0.2 
     Heroin 1.7a 1.7a 1.4  0.1  0.1  0.1  0.1  0.0  0.1 
     Hallucinogens 14.1  14.2  14.4  0.7  0.6  0.6  0.2  0.1  0.1 
          LSD 10.5  10.8  10.5  0.1  0.0  0.1  0.0  0.0  0.0 
          PCP 3.5  3.3  3.2  0.0  0.0  0.0  0.0  0.0 
          Ecstasy 2.6b 3.1  3.4  0.5  0.3  0.3  0.1  0.1  0.1 
     Inhalants 8.6  8.6  8.5  0.2  0.2  0.2  0.1  0.1  0.1 
     Nonmedical Use of Psychotherapeutics2 19.3  19.5  19.2  4.5  4.5  4.2  2.0  1.9  1.7 
          Pain Relievers 11.1  11.5  11.5  3.1  3.3  3.0  1.3  1.3  1.2 
               OxyContin® 0.5b 0.8  0.8  --  --  0.2  --  --  0.1 
          Tranquilizers 8.3  8.5  8.3  1.5  1.5  1.6  0.6  0.6  0.5 
          Stimulants 9.3a 9.0  8.6  0.8  0.6  0.7  0.4  0.3  0.3 
               Methamphetamine 5.7  5.7  5.3  0.4  0.4  0.4  0.2  0.2  0.2 
          Sedatives 5.1  4.8  4.9  0.4  0.3  0.2  0.2a 0.1  0.1 
ILLICIT DRUG OTHER THAN MARIJUANA1 29.3  29.3  28.8  6.0  5.9  5.6  2.7a 2.6  2.3 

50801 (2.1A REV)

 

Table A.6 Tobacco Product and Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 12 or Older: Numbers in Thousands, 2002-2004

Substance TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
TOBACCO PRODUCT1 171,838  172,843  171,827  84,731  83,415  83,066  71,499  70,757  70,257 
     Cigarettes 162,553  163,240  161,842  71,310  69,853  69,909  61,136  60,434  59,896 
     Smokeless Tobacco 46,870a 46,065  44,625  10,577  10,347  9,756  7,787  7,725  7,154 
     Cigars 88,053  88,096  87,409  25,928  25,386  25,974  12,751  12,837  13,727 
     Pipe Tobacco2 40,003  40,064  39,499  --  --  --  1,816  1,619  1,835 
ALCOHOL 195,452  197,533  198,220  155,476  154,540  156,686  119,820  118,965  120,934 
     Binge Alcohol Use3 --  --  --  --  --  --  53,787  53,770  54,725 
          Heavy Alcohol Use3 --  --  --  --  --  --  15,860  16,144  16,689 

50801 (2.1B REV)

 

Table A.7 Tobacco Product and Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 12 or Older: Percentages, 2002-2004
Substance TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
TOBACCO PRODUCT1 73.1b 72.7b 71.4  36.0b 35.1  34.5  30.4a 29.8  29.2 
     Cigarettes 69.1b 68.7b 67.3  30.3b 29.4  29.1  26.0a 25.4  24.9 
     Smokeless Tobacco 19.9b 19.4a 18.6  4.5a 4.4  4.1  3.3a 3.3  3.0 
     Cigars 37.4a 37.1  36.3  11.0  10.7  10.8  5.4  5.4  5.7 
     Pipe Tobacco2 17.0  16.9  16.4  --  --  --  0.8  0.7  0.8 
ALCOHOL 83.1  83.1  82.4  66.1  65.0  65.1  51.0  50.1  50.3 
     Binge Alcohol Use3 --  --  --  --  --  --  22.9  22.6  22.8 
          Heavy Alcohol Use3 --  --  --  --  --  --  6.7  6.8  6.9 

50801 (2.2B REV)

 

Table A.8 Tobacco Product and Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 12 to 17: Percentages, 2002-2004

Substance TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
TOBACCO PRODUCT1 36.8b 34.5b 32.7  23.6b 22.5  22.1  15.2  14.4  14.4 
     Cigarettes 33.3b 31.0b 29.2  20.3b 19.0  18.4  13.0a 12.2  11.9 
     Smokeless Tobacco 8.0b 7.6  7.1  4.3  4.1  4.3  2.0  2.0  2.3 
     Cigars 16.3b 15.1  14.8  10.1  10.0  10.2  4.5  4.5  4.8 
     Pipe Tobacco2 2.8  2.6  2.8  --  --  --  0.6  0.6  0.7 
ALCOHOL 43.4a 42.9  42.0  34.6  34.3  33.9  17.6  17.7  17.6 
     Binge Alcohol Use3 --  --  --  --  --  --  10.7  10.6  11.1 
          Heavy Alcohol Use3 --  --  --  --  --  --  2.5  2.6  2.7 

50801 (2.3B REV)

 

Table A.9 Tobacco Product and Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 18 to 25: Percentages, 2002-2004

Substance TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
TOBACCO PRODUCT1 75.5b 74.8a 73.5  54.9  53.8  54.3  45.3  44.8  44.6 
     Cigarettes 71.2b 70.2a 68.7  49.0a 47.6  47.5  40.8  40.2  39.5 
     Smokeless Tobacco 23.7b 22.0  21.4  8.0  7.8  8.0  4.8  4.7  4.9 
     Cigars 45.6a 45.2  44.1  22.7a 22.7a 24.0  11.0b 11.4b 12.7 
     Pipe Tobacco2 8.0  7.7  8.3  --  --  --  1.1  0.9a 1.2 
ALCOHOL 86.7  87.1  86.2  77.9  78.1  78.0  60.5  61.4  60.5 
     Binge Alcohol Use3 --  --  --  --  --  --  40.9  41.6  41.2 
          Heavy Alcohol Use3 --  --  --  --  --  --  14.9  15.1  15.1 

50801 (2.4B REV)

 

Table A.10 Tobacco Product and Alcohol Use in Lifetime, Past Year, and Past Month among Persons Aged 26 or Older: Percentages, 2002-2004
Substance TIME PERIOD
Lifetime Past Year Past Month
2002 2003 2004 2002 2003 2004 2002 2003 2004
TOBACCO PRODUCT1 77.7a 77.6a 76.4  34.5b 33.5  32.8  29.9a 29.3  28.5 
     Cigarettes 73.7a 73.6a 72.3  28.5  27.6  27.3  25.2  24.7  24.1 
     Smokeless Tobacco 20.9b 20.6  19.6  3.9b 3.8a 3.3  3.2a 3.2a 2.7 
     Cigars 39.0  38.7  37.9  9.1  8.7  8.6  4.6  4.5  4.6 
     Pipe Tobacco2 20.5  20.4  19.7  --  --  --  0.8  0.6  0.7 
ALCOHOL 88.0  88.0  87.3  68.4  67.0  67.2  53.9  52.5  53.0 
     Binge Alcohol Use3 --  --  --  --  --  --  21.4  21.0  21.1 
          Heavy Alcohol Use3 --  --  --  --  --  --  5.9  5.9  6.1 

50728 (5.25A REV)

 

Table A.11 Substance Dependence or Abuse for Specific Substances in the Past Year, by Age Group: Numbers in Thousands, 2002-2004
Past Year Dependence or Abuse Total AGE GROUP
12-17 18-25 26 or Older
2002 2003 2004 2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 7,116  6,835  7,298  1,376  1,287  1,347  2,548  2,486  2,684  3,192  3,062  3,267 
     Marijuana and Hashish 4,294  4,198  4,469  1,055  955  979  1,860  1,886  1,936  1,378  1,357  1,554 
     Cocaine 1,488  1,515  1,571  105  86  91  377  393  462  1,006  1,036  1,018 
     Heroin 214  189  270  13  12  21  47  42  70  153  135  179 
     Hallucinogens 426  321a 449  138  106  121  242  152a 214  46  63  114 
     Inhalants 180  169  233  101  104  134  29  41  52  50  25  47 
     Nonmedical Use of
        Psychotherapeutics
2
2,018  1,923  2,048  333  361  388  587  516b 652  1,098  1,046  1,008 
          Pain Relievers 1,509  1,424  1,388  237a 281  309  419  350a 454  853  793  624 
          Tranquilizers 509  435  573  87  96  75  144  147  154  278  192  344 
          Stimulants 436  378  470  98  98  86  137  142  172  202  138  212 
          Sedatives 154  158  128  28  40  22  26  20  24  100  99  82 
ALCOHOL 18,100  17,805  18,654  1,453  1,471  1,517  5,477  5,462  5,609  11,169  10,872  11,528 
ILLICIT DRUG OR ALCOHOL1 22,006  21,586  22,506  2,209  2,214  2,228  6,733  6,678  6,840  13,064  12,694  13,438 
BOTH ILLICIT DRUG AND ALCOHOL1 3,210  3,054  3,445  620  544a 635  1,292  1,270a 1,453  1,298  1,240  1,357 

50728 (5.25B REV)

 

Table A.12 Substance Dependence or Abuse for Specific Substances in the Past Year, by Age Group: Percentages, 2002-2004

Past Year Dependence or Abuse Total AGE GROUP
12-17 18-25 26 or Older
2002 2003 2004 2002 2003 2004 2002 2003 2004 2002 2003 2004
ILLICIT DRUG1 3.0  2.9  3.0  5.6  5.1  5.3  8.2  7.8  8.3  1.8  1.7  1.8 
     Marijuana and Hashish 1.8  1.8  1.9  4.3  3.8  3.9  6.0  5.9  6.0  0.8  0.7  0.8 
     Cocaine 0.6  0.6  0.7  0.4  0.3  0.4  1.2  1.2  1.4  0.6  0.6  0.6 
     Heroin 0.1  0.1  0.1  0.1  0.0  0.1  0.2  0.1  0.2  0.1  0.1  0.1 
     Hallucinogens 0.2  0.1a 0.2  0.6  0.4  0.5  0.8  0.5a 0.7  0.0  0.0  0.1 
     Inhalants 0.1  0.1  0.1  0.4  0.4  0.5  0.1  0.1  0.2  0.0  0.0  0.0 
     Nonmedical Use of Psychotherapeutics2 0.9  0.8  0.9  1.3  1.4  1.5  1.9  1.6a 2.0  0.6  0.6  0.6 
          Pain Relievers 0.6  0.6  0.6  1.0a 1.1  1.2  1.4  1.1a 1.4  0.5  0.4  0.3 
          Tranquilizers 0.2  0.2  0.2  0.4  0.4  0.3  0.5  0.5  0.5  0.2  0.1  0.2 
          Stimulants 0.2  0.2  0.2  0.4  0.4  0.3  0.4  0.4  0.5  0.1  0.1  0.1 
          Sedatives 0.1  0.1  0.1  0.1  0.2  0.1  0.1  0.1  0.1  0.1  0.1  0.0 
ALCOHOL 7.7  7.5  7.8  5.9  5.9  6.0  17.7  17.2  17.4  6.2  6.0  6.3 
ILLICIT DRUG OR ALCOHOL1 9.4  9.1  9.4  8.9  8.9  8.8  21.7  21.0  21.2  7.3  7.0  7.3 
BOTH ILLICIT DRUG AND ALCOHOL1 1.4  1.3  1.4  2.5  2.2  2.5  4.2  4.0a 4.5  0.7  0.7  0.7 

End Note

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

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