Cigarette and Cannabis Use in Young Swiss Men: Examination of the Bidirectional, Longitudinal Associations Between Frequency of Use and Descriptive Norms.

OBJECTIVE: Although several studies have investigated longitudinal associations between social norms and alcohol use behaviors, less is known about associations between social norms and use of other substances, such as cigarettes and cannabis. The present study aimed to examine the temporal ordering of descriptive norms and cigarette and cannabis use over time.

METHOD: A sample of 5,158 young Swiss men from the Cohort Study on Substance Use Risk Factors (C-SURF) completed baseline and 15-month follow-up questionnaires assessing frequency of use and descriptive norms of cigarette and cannabis use. Bidirectional, longitudinal associations between descriptive norms and cigarette and cannabis use were examined using cross-lagged panel models.

RESULTS: Descriptive norms for cigarette use at baseline predicted increased frequency of use at follow-up, whereas the opposite association, from frequency of cigarette use at baseline to descriptive norms at follow-up, was not significant. For cannabis, associations between descriptive norms and frequency of use were reciprocal. Descriptive norms at baseline predicted an increased frequency of cannabis use at follow-up, and frequency of cannabis use at baseline predicted a later increase in descriptive norms.

CONCLUSIONS: For cigarette use, findings suggest that descriptive norms shape later cigarette use behaviors. For cannabis use, findings suggest that descriptive norms shape cannabis use, but cannabis use also shapes later descriptive norms.