Risk and Protective Factors for Adolescent Drug Use:
Findings from the 1999 National Household Survey on Drug Abuse

Chapter 1. Introduction

1.1 Overview

Risk and protective factors refer to variables in youths' neighborhoods, families, school, and peer groups, as well as to factors within the individual, that increase or decrease the likelihood of problem behaviors (Catalano, Hawkins, Berglund, Pollard, & Arthur, 2002). Risk factors for substance use (e.g., high rates of substance use among peers) typically are associated with an increased likelihood of substance use, whereas protective factors for substance use (e.g., communication with parents about the dangers of substance use) are related to a decreased likelihood of substance use. Addressing both risk and protective factors in substance use prevention programs is believed to be an important determinant of program success (Center for Substance Abuse Prevention [CSAP], 2001).

This report presents data from the 1999 National Household Survey on Drug Abuse (NHSDA) relating to several aspects of risk and protective factors for substance use among youths aged 12 to 17. These include the following:

• distribution of risk and protective factors among youths;



• associations between individual risk and protective factors and youth substance use;



• relative predictive power of different categories (or "domains") of risk and protective factors in predicting youth substance use;



• examination of the effect of family and neighborhood characteristics on youth substance use based on the hierarchical nature of these data; and



• changes in risk and protective factors over time, and the relation of this change to observed changes over time in the prevalence of youth substance use.

1.1.1 Related Prevention Literature

The role of risk and protective factors has been a major focus in the research on youth substance use for more than 20 years. Perhaps the most influential review of risk and protective factors related to youth substance use was conducted by Hawkins, Catalano, and Miller (1992) of the Social Development Research Group, School of Social Work, University of Washington, Seattle. This review article is widely cited and provides one of the most comprehensive and rigorous assessments of the research to date. Other major reviews of the risk and protectivefactor literature were conducted by Petraitis, Flay, Miller, Torpy, and Greiner (1998) and Botvin, Botvin, and Ruchlin (1998). Botvin and colleagues reviewed the effectiveness of selected substance use prevention programs, classifying the programs into four types of approaches: information dissemination, affective education, social influence, and comprehensive or expanded social influences. Information dissemination approaches provide information about the risks of substance use, and affective education approaches focus on personal and social development. Both information dissemination and affective education approaches have been shown to have little or no effect in reducing substance use due to their narrow focus. Social influence and integrated social influence approaches have, however, been shown to be effective. Social influence approaches involve persuasive messages from peers and the media, and integrated social influence/competence enhancement approaches teach self-management, social, cognitive, self-esteem enhancing, adaptive coping, and general assertiveness strategies and skills. Each of these latter two approaches has been linked to significant reductions in the use of cigarettes, alcohol, and illicit drugs.

A recent review of science-based substance abuse prevention programs (i.e., those that have been shown through rigorous scientific evaluation to reduce substance use), including a comprehensive review of risk and protective factors related to substance use, was published by CSAP (2001). In this review, as in most reviews of this literature, risk and protective factors were divided into a series of life areas or "domains" in order to reflect how these factors extend across multiple facets of youths' lives. The CSAP review indicated that successful substance abuse prevention programs have typically been programs that can decrease risk factors and increase protective factors across multiple domains.

1.1.2 Relation to Earlier Report on Risk and Protective Factors for Adolescent Drug Use: Findings from the 1997 NHSDA

The NHSDA provides estimates of the prevalence, incidence, demographic and geographic distribution, and correlates of use of illicit drugs, alcohol, and tobacco in the civilian, noninstitutionalized U.S. population 12 years of age or older. The survey gives particular emphasis to collecting information on youths by oversampling 12 to 17 year olds and by using questionnaire modules designed exclusively for youths. In 1997, a new module was added for 12 to 17 year olds to examine risk and protective factors related to substance use. In 1998, and again in 1999, the module on risk and protective factors was expanded and improved. The 1999 NHSDA included a comprehensive set of risk and protective factor items based on the extensive review of risk and protective factors for youth substance use by Hawkins et al. (1992).

A report based on the risk and protective factors measured in the 1997 NHSDA was published by the Office of Applied Studies (OAS) in February 2001 (Lane, Gerstein, Huang, &Wright, 2001). The present report updates, expands, and improves on the information in the 1997 report in a number of ways.

• First, the 1999 sample (66,706 persons aged 12 or older, with 25,357 youths aged 12 to 17) was much larger than the 1997 sample (24,505 persons aged 12 or older, with 7,844 youths aged 12 to 17); therefore, the precision of the estimates was improved.



• Second, the number of questions was expanded, providing data on a more comprehensive set of risk and protective factors.⁴ This expansion of the number of questions also allowed for the construction of multiple-item scales to measure many of the individual factors, as opposed to the single items used in the previous report. (See the tables in Chapter 2 for the distribution of risk and protective factors for the Nation as a whole and by age, race/ethnicity, and gender.)



• Third, the analyses were extended to explore risk and protective factors in a hierarchical model, reflecting the nested nature of youths living in households that in turn comprise neighborhoods. Hierarchical modeling and analysis have been described by Goldstein (1995), Snijders and Bosker (1999), and Raudenbush and Bryk (2002).⁵



• Fourth, a discussion of trends was included assessing how risk and protective factors may have changed over 2 years, both with respect to the distribution of the factors and to the strength of their associations with the use of marijuana. Also discussed is the extent to which the decrease in the prevalence of marijuana among youths may be attributable to changes in the distribution of the factors or their association with marijuana use.

The classification approach used in this report categorizes the set of risk and protective factors into one of four domains based on the categories presented by Hawkins et al. (1992): community, family, peer/individual, and school. The 1999 NHSDA questionnaire included specific items drawn from the research literature on prevention related to each of these domains. The factors in each domain are discussed in Chapter 2, and a complete list of the questions and response categories included in the analyses is presented in Tables A.1 to A.4 (see Appendix A). The community domain includes such factors as community disorganization and crime and the availability of illicit drugs. The family domain includes such factors as parental attitudes toward youth substance use and parental communication with youths about the dangers of substance use. The peer/individual domain includes such factors as antisocial behavior and friends' use of licitand illicit drugs. The school domain includes such factors as sanctions against substance use at school and exposure to prevention messages in school. Most of the items addressing these factors were designed for and asked only of the 12 to 17 year olds in the sample. Most items focused on current or past year perceptions or on past year behavior.

1.1.3 Organization of the Report

Chapter 1 provides a general introduction to the NHSDA methodology and the organization of the risk and protective factors included in this report.

Chapter 2 looks at the prevalence of the various risk and protective factors in the population as a whole and by demographic variables, such as race/ethnicity, gender, and age.

Chapter 3 examines the associations between these factors and past year marijuana use.

Chapter 4 explores the relative predictive power of risk and protective factors, both individually and by domain, in a multiple logistic regression analysis. It also attempts to develop the best model to "predict" youth marijuana use, based on a reduced set of risk and protective factors from all four domains. Finally, it explores the extension of modeling to explain variation at higher levels of the hierarchical structure (i.e., families and communities), including a brief general introduction to hierarchical modeling. Models of cigarette use and alcohol use are also presented in selected tables.

Chapter 5 discusses some methods and issues associated with measuring the change in risk and protective factors over time, and it compares the distributions of risk and protective factors from 1997 to 1999 and the associations between these risk and protective factors and marijuana use for these 2 years.⁶ It also discusses how changes in the distribution of risk and protective factors and changes in the strength of association between the risk and protective factors and marijuana use between 1997 and 1999 may explain the decrease in youth marijuana prevalence rates during this period.

Chapter 6 discusses the final conclusions from this report.

Consistent with the 1997 report (Lane et al., 2001), the analyses in this report focus on past year marijuana use. Selected analyses are presented for alcohol and cigarette use in Chapter 4. Analyses were not conducted on the use of illicit drugs other than marijuana because few ofthe questions focused specifically on youths' attitudes, beliefs, and behaviors specific to those substances. Unless otherwise stated, all statements in the text regarding statistical associations between variables or differences between groups have been tested at the .05 level.

A directory of the prevention domains, constructs, and individual questions used to measure risk and protective factors is presented in Appendix A. A discussion of missing data for questions relating to the school domain is presented in Appendix B. A discussion of how risk and protective factors and substance use differ by age is presented in Appendix C. Further information about methodological changes between the 1997 and 1999 NHSDAs that impacted the comparison of youth prevalence rates for marijuana in those 2 years is presented in Appendix D. Comparisons of the wording, distributions, and associations with marijuana use of the risk and protective factors measured using similar, but not identical, questions in 1997 and 1999 are presented in Appendix E.

1.2 Overview of the NHSDA Methodology

The NHSDA is a primary source of statistical information on the use of illicit 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 place of residence. The survey is sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA), and data collection is carried out by RTI in Research Triangle Park, North Carolina, under a contract with SAMHSA's Office of Applied Studies (OAS). This section briefly describes the 1999 NHSDA methodology. A more complete description is provided in another SAMHSA report (OAS, 2000).

The survey covers residents of households, noninstitutional group quarters (e.g., shelters, rooming houses, dormitories), and civilians living on military bases. Persons excluded from the survey include homeless people who do not use shelters, active military personnel, and residents of institutional group quarters, such as jails and hospitals.

1.2.1 Redesign of the NHSDA

Prior to 1999, the NHSDA was conducted using a paper-and-pencil interviewing (PAPI) methodology, and the interviews generally lasted about an hour. The 1999 NHSDA marked the first survey year in which the national sample was interviewed via computer-assisted interviewing (CAI; specifically, a combination of computer-assisted personal interviewing [CAPI] and audio computer-assisted self-interviewing [ACASI] techniques). For the most part, questions previously administered by the interviewer are now administered by the interviewer using CAPI. Questions previously administered using answer sheets are now administered using ACASI. Use of ACASI is designed to provide the respondent with a highly private and confidential means of responding so as to maximize honest reporting of illicit drug use and other sensitive behaviors. In 1999, the sample size was increased from approximately 25,500 persons in 1998 (6,778 youths aged 12 to 17) to 66,706 persons in 1999 (25,357 youths aged 12 to 17).

The 1999 NHSDA employed a 50-State design with an independent, multistage area probability sample for each of the 50 States and the District of Columbia. The eight States with the largest population (which together account for 48 percent of the total U.S. population aged 12 or older) were designated as large sample States (California, Florida, Illinois, Michigan, New York, Ohio, Pennsylvania, and Texas). For these States, the design provided a sample large enough to support direct State estimates. For the remaining 42 States and the District of Columbia, smaller, but adequate, samples were selected to support State estimates using small area estimation (SAE) techniques. 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.

Due to differential sampling rates among the 50 States and the District of Columbia and across the age groups of interest, sampling weights are needed to produce the correct population estimates. In addition to reflecting the probability of selection, the sample weights also incorporate other adjustments for nonresponse, control of extreme weights, and poststratification to known population totals. For some key variables that still had missing values after the editing process, values were statistically imputed. The sampling weights have been used in all analyses in this report except for the hierarchical modeling. For more information on statistical procedures used in the NHSDA, see the reports on the results from the 1999, 2000, and 2001 NHSDAs (OAS, 2000, 2001, 2002a, 2002b).

1.2.2 1999 CAI and 1999 PAPI

To assess the impact of the change in data collection mode from PAPI to CAI and to measure trends in substance use, the 1999 survey utilized a dual-sample design. The main sample of 66,706 respondents was interviewed using the CAI methodology, while an additional 13,809 supplemental interviews were conducted via the PAPI methodology. The intent was to use the 1999 PAPI data to measure changes in use patterns because the methodology was the same as was used in prior years. The supplement was selected from a national subsample of 250 geographic strata. Both the main (CAI) and supplemental (PAPI) surveys were conducted from January through December 1999. With the exception of comparisons between the 1997 and 1999 surveys that are presented in Chapter 5, all analyses presented in this report utilized the 1999 computer-based interview. More information about the 1999 PAPI is presented in Chapter 5.

This page was last updated on July 17, 2008.

SAMHSA, an agency in the Department of Health and Human Services, is the Federal Government's lead agency for improving the quality and availability of substance abuse prevention, addiction treatment, and mental health services in the United States.