Reliability and validity of the Japanese version of the Biological Rhythms Interview of Assessment in Neuropsychiatry-self report for delayed sleep-wake phase disorder

Abstract Objective The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) might be applicable for assessing delayed sleep-wake phase disorder (DSWPD). We aimed to investigate the reliability and validity of the Japanese version of the BRIAN self-report (J-BRIAN-SR) in DSWPD patients and determine a cutoff score to identify the presence of the disorder. Methods We enrolled 60 newly diagnosed DSWPD outpatients and 64 age-matched healthy controls. We used Cronbach's alpha for internal reliability to evaluate J-BRIAN-SR. We confirmed the reliability of the A test and re-test using Pearson’s correlation coefficient in the controls. We used confirmatory factor analysis to evaluate the factor structure of J-BRIAN-SR and referenced the Morningness-Eveningness Questionnaire (MEQ) to check concurrent validity. We analyzed the receiver operating characteristic curve (ROC) to determine the J-BRIAN-SR cutoff point for the presence of DSWPD. Results The 18-component scores of the J-BRIAN-SR had an overall reliability coefficient (Cronbach's alpha) of 0.82. We confirmed a high test-retest reliability using an intraclass correlation coefficient (r = 0.84). The correlation between J-BRIAN-SR and MEQ was 0.38 (p = 0.003). The J-BRIAN-SR that we extracted by exploratory factor analysis consisted of three factors. A score of 40 points provided a sensitivity of 80.0% and a specificity of 75.6% for the positivity of DSWPD. Conclusions The results of the present study revealed that J-BRIAN-SR is a valid and reliable instrument for screening and evaluating the severity of DSWPD. Our findings will be useful to physicians and patients in Japan and those in clinical settings.