We combined abuse and dependence into one outcome, since empirical findings indicate that it better captures the underlying prevalence of cannabis use disorders than dependence or abuse alone. While substance use disorders were originally conceived as a bi-axial syndrome with dependence capturing more physiologic dimensions of addiction and abuse capturing more behavioral consequences, there is now substantial evidence to indicate that abuse and dependence criteria, including cannabis use disorder criteria, represent a unidimensional construct (Beseler and Hasin, 2010; Helzer et al., 2007; Li et al., 2007; Martin et al., 2006; Martin et al., 2008; Saha et al., 2006).
