We reviewed UNODC data [41] but could not identify any cannabis-related indicators relevant for public health monitoring that are not already captured by the EMCDDA data collection. In fact, both agencies collect data on prevalence of use and on treatment rates. However, we chose to refer to EMCDDA data for the following reasons: the UNODC ‘general population’ prevalence database does not include information on the age range of the target population or exact references. Further, it contains several estimates derived from the school survey initiative ESPAD, which should not be reported as general population estimates. As for TDI, we compared data from UNODC and EMCDDA for 2017 for 16 countries with data available in both data bases. For any drug treatment, data were only consistent in half of the countries. Further, treatment demand for CUD was only reported as percentage of all treatment demand in the UNODC data base, requiring recalculations and additional assumptions to report CUD treatment rates. Based on this assessment, we restricted our analyses to data provided by the EMCDDA.
