The structure of cannabis dependence in the community

Background: Cannabis is the most widely used illicit drug in developed countries, and has a significant impact on mental and physical health in the general population. However, the validity of common diagnostic schemes and their applicability to cannabis abuse and dependence is poorly understood. This paper describes a confirmatory factor analysis of the DSM-IV cannabis abuse and dependence criteria, using general population data. Methods: Data from cannabis users (n=722) were obtained from a cross-sectional study of a large and representative sample of the Australian general population. The DSM-IV criteria for cannabis abuse and dependence were assessed using the CIDI-AUTO. Results: Approximately, one in 12 Australians (7.1%) had used cannabis more than five times in the past 12 months and 56.5% of these reported at least one DSM-IV cannabis abuse or dependence criteria. Within the adult population, 2.2% met criteria for a cannabis use disorder (0.7% abuse and 1.5% dependence). Confirmatory factor analysis indicated that both a one- and two-factor model for cannabis use disorder provided an adequate fit to the data. However, the estimated correlation between the abuse and dependence factors in the two-factor model was extremely high (0.99). Conclusions: A one-factor model provided the most parsimonious model of the cannabis abuse and dependence criteria.