Childhood trauma is prevalent in the US, and individual types as well as the total number experienced are associated significantly with marijuana and cocaine use throughout the life-course, a recent study found. Researchers utilized a nationally representative sample of individuals in grades 7–12 (aged 11–21 years) during 1994–95, who were re-interviewed during emerging adulthood (2001–02; aged 18–28) and adulthood (2007–08; aged 24–34). The analytical sample comprised 12,288 participants with data at all 3 waves. They found:

• Approximately half experienced at least 1 childhood trauma; traumas were not highly correlated.
• There was a dose-response relationship between the number of traumas and drug use in adolescence.
• Similar dose-response relationships with drug use were observed in emerging adulthood and adulthood.
• Each individual trauma was associated independently with either marijuana or cocaine use in adolescence, emerging adulthood, and/or adulthood.