In contrast to all other trends, the prevalence of CUD did not show indications of increases in Europe. As the CUD data constitute smoothed estimates obtained from statistical models, there are some problems inherent to these data, such as not appropriately representing the true fluctuation in the data. However, as CUD prevalence is estimated from cannabis use prevalence, the diverging trends question the validity of the CUD estimates. The consistency of select GBD estimates have been questioned in previous studies (e.g., [67,68]) and our results add that estimation procedures for CUD prevalence may be revisited and improved. An additional consideration is that the validity of CUD estimates may vary between countries, which limits comparability of estimates across countries.
