Confirming alcohol-moderated links between cannabis use and dependence in a national sample.

The present study confirmed findings that alcohol moderates the link between cannabis use and dependence. The study examined a large, diverse national sample of 856 people who consumed cannabis and alcohol at least twice per week. The study possesses several methodological improvements over past research, including less subjective measures of cannabis use and interview-based data collection. Cannabis use and alcohol consumption interacted to predict cannabis dependence symptoms. Cannabis use covaried with cannabis dependence particularly in people who consumed greater amounts of alcohol. These data further support the hypothesis that alcohol increases problems associated with cannabis use.