Third, the eligibility of dependence diagnoses as the "gold standard" itself needs to be discussed. There is still a controversy about the way in which the drug (and especially the cannabis) dependence syndrome should be operationalized in future diagnostic systems like DSM-V, which is currently being prepared. For example, it has been argued that the rule of three criteria that has been defined for alcohol and opiate dependence may be over-inclusive for cannabis [36,37]. Others emphasize psychological components or behavioural indicators of dependence [37] or propose dimensional equivalents for the so far categorically defined substance use disorders [38].
