This paper builds on our systematic reviews of the epidemiology of cannabis use and dependence[29-32], and the relationship between cannabis use and schizophrenia[24,30,33], and expands on previous analyses of the contribution of illicit drug use to the global burden of disease[27,28,34-36]. We expand considerably in this paper on what has been previously reported by conducting the first assessment of the global burden of cannabis dependence. We 1) outline the methodology used to estimate burden for this disorder specifically; 2) assemble data on the incidence and prevalence of cannabis use and dependence into a comprehensive disease model which adjusts for known sources of variability between studies; 3) investigate trends in the burden of cannabis dependence; and finally 4) investigate the model used in GBD 2010 to estimate the global burden of disease attributable to cannabis dependence as a risk factor for schizophrenia.
