Inter-observer reliability of DSM-5 substance use disorders

Although studies have examined the impact of changes made in DSM-5 on the estimated prevalence of substance use disorder (SUD) diagnoses, there is limited evidence concerning the reliability of DSM-5 SUDs. We evaluated the inter-observer reliability of four DSM-5 SUDs in a sample in which we had previously evaluated the reliability of DSM-IV diagnoses, allowing us to compare the two systems. Methods: Two different interviewers each assessed 173 subjects over a 2-week period using the Semi-Structured Assessment for Drug Dependence and Alcoholism (SSADDA). Using the percent agreement and kappa (κ) coefficient, we examined the reliability of DSM-5 lifetime alcohol, opioid, cocaine, and cannabis use disorders, which we compared to that of SSADDA-derived DSM-IV SUD diagnoses. We also assessed the effect of additional lifetime SUD and lifetime mood or anxiety disorder diagnoses on the reliability of the DSM-5 SUD diagnoses. Results: Reliability was good to excellent for the four disorders, with κ values ranging from 0.65 to 0.94. Agreement was consistently lower for SUDs of mild severity than for moderate or severe disorders. DSM-5 SUD diagnoses showed greater reliability than DSM-IV diagnoses of abuse or dependence or dependence only. Co-occurring SUD and lifetime mood or anxiety disorders exerted a modest effect on the reliability of the DSM-5 SUD diagnoses. Conclusions: For alcohol, opioid, cocaine and cannabis use disorders, DSM-5 criteria and diagnoses are at least as reliable as those of DSM-IV.