Psychometrics of the kiddie schedule for affective disorders and schizophrenia present and lifetime version for DSM‐5 in Japanese outpatients

Abstract Objective The Schedule for Affective Disorders and Schizophrenia for School‐Age Children‐Present and Lifetime version (K‐SADS‐PL) is a widely used semi‐structured diagnostic interview in child and adolescent psychiatry. However, the psychometric properties of its updated version, the K‐SADS‐PL for DSM‐5, have scarcely been examined, especially for criterion validity. This study was designed to examine the inter‐rater reliability, criterion validity and construct validity of the K‐SADS‐PL for DSM‐5 in 137 Japanese outpatients. Methods Two of 12 experienced clinicians independently performed the K‐SADS interview for each patient in a conjoint session, and the resulting consensus diagnosis was compared with a “best‐estimate” diagnosis made by two of eight experienced clinicians using all available information for the patient. Results The inter‐rater reliability was excellent, as shown by κ > 0.75 for all disorders, with the exception of current separation anxiety disorder. The criterion validity was fair to good, as shown by κ > 0.40 for all disorders, with the exception of current and lifetime agoraphobia. The construct validity was also good, as shown by theoretically expected associations between the K‐SADS‐PL diagnoses and subscales of the child behavior checklist. Conclusion The K‐SADS‐PL for DSM‐5, now available in Japanese, generates valid diagnoses in child and adolescent psychiatry