Conceptualizing the influence of alcohol and marijuana use on intentions to have sex using the Integrative Model

The link between substance use and sexual behavior has been established in the literature, at both levels of global and event-specific associations (Beadnell et al., 2007; Cooper, 2002). The cognitive mechanism by which alcohol or marijuana use influences sexual activity, however, has not been consistently documented (Beadnell et al., 2008, for an example).

Using the Integrative Model (Fishbein, 2000), this study examines the processes by which alcohol and marijuana use influence intentions to have sex among a sample of adolescents in Philadelphia. A total of 458 White and African American adolescents, ages 14 to 16, provided information about their attitudes, perceived norms, self-efficacy and intentions to have sex in the next 12 months, and also reported on their alcohol use during the last 12 months and their lifetime marijuana use.

Results indicate that alcohol use increases intentions to have sex through self-efficacy, while marijuana use increases intentions indirectly through attitudes, norms, self efficacy, and also with a direct effect. In addition, while marijuana use does not moderate the theoretical links between intentions, attitudes, norms and self-efficacy, alcohol use increases the magnitude of the links between intentions and both attitudes and self-efficacy. Thus, while non-alcohol users base their intentions on attitudes and perceptions of norms, alcohol users base their intentions on attitudes, norms and self-efficacy.

In conclusion, the link between alcohol use and intentions to have sex appears to be different for alcohol-users than for those non-alcohol users.