An Evaluation of the Gateway Model as a Basis for Adolescent Alcohol and Substance Abuse Policy - Part II
» Project Details
This project seeks to improve the utility of a "stages" or "gateway" theory adolescent substance use by advancing our ability to measure and monitor the probabilities of youthful substance use progression. Extensive prior research has identified a gateway phenomenon whereby youths tend to progress through a series of substances starting with alcohol and/or tobacco, followed by marijuana and then hard drugs. Individuals who use substances at one stage risk progression to the next Individuals who do not use substance at one stage rarely ever use those associated with a later stage. The gateway theory has served as the cornerstone for much substance abuse prevention policy. Despite the clarity of the theory, however, accurate information about the probability of progression to each stage has not been readily available nor is it easily derived from the statistics on youthful substance use routinely collected and reported. Estimates of the probabilities of progression at each stage and their covariates hold promise to provide a more precise foundation for the formulation of the most effective and cost-effective drug-abuse prevention policies.
Under a previous grant from the Robert Wood Johnson Foundation Substance Abuse Policy Research Program, the authors developed a procedure for estimating these probabilities using data from the National Household Survey on Drug Abuse. In addition to advancing the research technology, findings from that study support the following policy-relevant claims:
A. Youths initiating marijuana use in the 1990s are much less likely to progress to cocaine and heroin than marijuana users in prior generations. This finding suggest that the dramatic increase in youthful marijuana use starting in the mid-1990s does not foretell the coming of a new epidemic of hard drug use, at least so far.
B. Initiation of alcohol use tends to occur most often at three different ages, 12, 15,and 18. This finding supports the need to provide alcohol awareness and prevention programs at multiple and distinct ages; and
C. Initiation of alcohol, tobacco and marijuana use at early ages is associated with increased risk of hard drug use. This
finding suggests that prevention programs should most strongly target use before age 15 and that services to early
substance users might reduce more hard drug abuse than primary prevention programs for older youths.
This project will investigate the following specific aims that advance our ability to employ a stage theory of substance use
progression in public policy formation:
1. Examine the utility of a stages perspective in high-risk communities.
2. Expand the procedure to incorporate hallucinogens, tranquilizers, inhalants, and other drugs, as well as progression to regular use, problem use and desistence.
3. Refine the estimation procedure through further research into non-disclosure, forward telescoping and the relationship between progression and high school dropout.
The project work will greatly expand our understanding of the nature of substance use progression, the extent to which it is culturally embedded, and how it varies across locations and over time. This work will guide the interpretation of trends in youthful substance use, help identify appropriate prevention strategies and evaluate the impact of current prevention initiatives.