Abstract
In a sample of 294 first-admission psychotic subjects participating in an epidemiologic study, a diagnosis of comorbid psychoactive substance use disorder (PSUD) was made less frequently by clinicians at the treating facilities (17.7%) than by the research diagnosticians (28.9%). The level of agreement was moderate (kappa = 0.49), and the clinical diagnoses showed high specificity (0.95) but low sensitivity (0.48). Concordance between clinical and research diagnosis of PSUD was not significantly associated with demographic or clinical characteristics; the major reason for the discordance was criterion variance.