Stepping through the drug use sequence: longitudinal scalogram analysis of initiation and regular use.

Using a new technique for tracing the sequence of use over time, this study examined the pattern of drug involvement among 4,145 West Coast adolescents over the 4-year span from Grades 7-10. During the period covered, the mid- to late 1980s, we found no evidence that cocaine has become a gateway drug. However, the data provided some support for treating cocaine initiation as a separate stage that precedes the onset of hard drugs other than pills. The analysis also showed that increased involvement with legal drugs constitutes an important step in the transition to hard drug use for most adolescents. Weekly alcohol use followed marijuana use and preceded use of all other illicit drugs for Hispanic, White, and Black youth. However, it followed use of hard drugs for Asians. Weekly smoking formed a distinct stage between initial use of pills and other hard drugs for non-Hispanic Whites. The results underscore the importance of prevention efforts aimed at curbing the transition to regular use of alcohol and cigarettes, as well as their initial use.