An evaluation of the proposed DSM-5 cannabis use disorder criteria using Australian national survey data.

OBJECTIVE: The aim of the current study was to evaluate the proposed cannabis use disorder criteria for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) using epidemiological data.

METHOD: Data came from the 2007 Australian National Survey of Mental Health and Wellbeing. Lifetime DSM-IV and DSM-5 cannabis use disorder diagnoses were assessed using a modified version of the World Mental Health Composite International Diagnostic Interview among those respondents who had used cannabis more than five times (n = 1,639; 37% female).

RESULTS: The prevalence of cannabis use disorder decreased from DSM-IV (6.2%) to DSM-5 (5.4%). Two fifths of those with DSM-IV cannabis abuse would fall below the threshold for DSM-5 cannabis use disorder. More than a third of those classified as DSM-IV "diagnostic orphans" would meet criteria for a DSM-5 mild, moderate, or severe cannabis use disorder. In terms of demographic and clinical characteristics, those who converted from no disorder in DSM-IV to a disorder under DSM-5 were similar to those diagnosed with a disorder according to both systems. Those who converted to no disorder under DSM-5 tended to be young men with cross-substance involvement and high levels of cannabis consumption.

CONCLUSIONS: Although a previous study of the Australian population found that alcohol use disorders increase considerably under DSM-5, the current study found a reduction in cannabis use disorders in the transition from DSM-IV to DSM-5. This is likely the result of the high ratio of cannabis abuse to dependence when compared with other substances. Given the implications the proposed changes have on the epidemiology of substance use disorders, further research is needed to determine whether the proposed criteria are optimal.