This article examined substance use and sexual behavior by conducting an analysis of college students' reported behaviors using a daily diary approach. By isolating particular sexual events across a 2-month period, we examined situational predictors of engagement in sex and of negative sexual experiences (coerced sex and/or sex that lacks perceived control) for college men and women. Data come from the daily diary sub-study of the Sexual Health Initiative to Foster Transformation. These data include 60 days of daily responses from 420 undergraduates at one New York City institution. This was a relatively diverse sample comprised of 49% women, 28% identifying as non-heterosexual, 60% non-white, and a roughly equal number of college freshman, sophomores, juniors, and seniors. Analyses examined the effects of alcohol use, binge drinking, marijuana use, and other drug use on sexual experiences. Between-person and within-person substance uses were related to an increased likelihood of having at least one sexual encounter during the study period. After adjusting for each participants' average substance use, both the number of alcoholic drinks consumed (AOR 1.13 (1.05-1.21)) and binge drinking scores (AOR 2.04 (1.10-3.79)) increased the likelihood of negative sex. Interaction analyses showed that compared to men, women were more likely to use alcohol and marijuana prior to sexual encounters. Given that sex and substance use are co-occurring, current prevention approaches should be paired with strategies that attempt to prevent negative sexual experiences, including sexual assault, more directly. These include consent education, bystander training, augmentation of sexual refusal skills, and structural change. Efforts promoting increased sex positivity might also help make all students, and women in particular, less likely to use substances in order to facilitate sex.
Keywords: Alcohol use; College students; Drug use; Event-level analysis; Sexual behavior.