In recent years, trend data from consecutive cross-sectional surveys in a variety of European countries have shown a general increase in the prevalence of cannabis use, particularly among the younger generations [1,2]. While, in most cases, consumption patterns remain experimental or occasional [3,4], the increasing prevalence may imply that a growing fraction of users will experience adverse consequences on mental and physical health or on a social level. Early identification of cannabis users at risk for negative consequences is of considerable value and the demand for appropriate and efficient screening instruments is increasing. A methodologically sound indicator would be useful for both epidemiological and clinical purposes. In the first case, screening scales could help to identify risk factors in order to prevent cannabis-related problems before they will cause serious health or other adverse consequences in a large number of people. This knowledge could guide the development and evaluation of public health policies. In the second case, based on the individual level of risk, users that have not yet entered the treatment system could be allocated to brief early interventions. Moreover,
