the modest differences in the prevalence of SUD diagnoses between DSM-IV and DSM-5. The identification of valid biomarkers for SUD disorders would potentially enhance both the reliability and validity of SUD diagnoses, although to date, all DSM diagnoses have depended on self-reported information. Finally, the presence of control subjects reduced the prevalence of SUDs in our sample. However, analysis of the subsample recruited as affected cases showed that, as for the full sample, the rates of switching for alcohol and opioids between diagnoses from one system to the other were nearly equal, while the tendency to switch from no diagnosis under DSM-IV to a diagnosis under DSM-5 was more significant for cocaine and cannabis. The sample was comprised predominantly of individuals at the extremes of the diagnostic continuum, which could have limited the extent of diagnostic switching. A sample with a different distribution of criterion endorsement could show more diagnostic switching.
