We also directly compared these characteristics across D4-only and D5-only (Table 2, right-most column): if DSM-5 criteria represent a more valid diagnosis, we would expect a difference in clinical characteristics across these groups, with D5-only exhibiting more severe phenotypes. For most of the features examined, individuals in D4-only exhibited slightly – but not significantly – higher prevalence/severity (e.g., a younger age of onset of symptoms) than those in D5-only. Differences across the groups in the prevalence of cannabis abuse/dependence did reach significance. Furthermore, z-statistics provide some evidence that, with regards to externalizing disorders (e.g., conduct disorder, illicit drug diagnoses), D4-only is less different from D4D5 than is D5-only. These differences, however, do not meet significance criteria in the direct comparison.
