Objective: To investigate the reliability of the Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia (WASH-U-KSADS) mania and rapid cycling sections.

Method: The 1986 version of the KSADS was modified and expanded to include onset and offset of each symptom for both current and lifetime episodes, expanded prepubertal mania and rapid cycling sections, and categories for attention-deficit/hyperactivity disorder and other DSM-IV diagnoses. To optimize diagnostic research, skip-outs were minimized. Subjects participated in the ongoing "Phenomenology and Course of Pediatric Bipolar Disorder" study. Mothers and children were interviewed separately by research nurses who were blind to diagnostic group status. In addition, ratings of off-site child psychiatrists, made from the narrative documentation given for each WASH-U-KSADS item, were compared with research nurse ratings. This work was performed between 1995 and 2000.

Results: There was 100% interrater reliability, five consecutive times, as both interviewer and observer after 10 to 15 trials. The kappa values of comparisons between research nurse and off-site blind best-estimate ratings of mania and rapid cycling sections were excellent (0.74-1.00). High 6-month stability for mania diagnoses (85.7%) and for individual mania items and validity against parental and teacher reports were previously reported.

Conclusions: The WASH-U-KSADS mania and rapid cycling sections have acceptable reliability.