Patterns of primary drug abuse.

This study focuses on the relationship between patterns of primary drug abuse during 1976 for heroin, marijuana, cocaine, and amphetamines across the demographic variables of age at first use, education, race/ethnic, and sex. A sample of 162,062 clients was selected. Findings indicate that marijuana usage followed by heroin, amphetamines, and cocaine is the most common pattern for clients whose age at first use is 15. Clients with an age at first use of 16 show a pattern of heroin followed by marijuana, amphetamines, and cocaine. Blacks abuse heroin to a greater extent that either White or Spanish-speaking clients.