Student substance use: stability and change across college years.

Entering freshmen, second-semester freshmen, and sophomores through seniors were surveyed regarding their recent alcohol and drug use. Among entering freshmen, 81% drank and 34% used drugs. Compared to groups that had been at college longer, entering freshmen were a significant 16% lower for alcohol and 12% lower for drugs than the other groups, but all other groups showed no significant differences regardless of year in school. When analyzed separately by sex, all results were identical to this overall pattern except that drug use among women did not appear to increase substantially from entering students to later years. These results indicate a relatively rapid influence of the college environment which then leads to stability of substance use behavior.