Reliability, validity and clinical utility of a Japanese version of the Social Adaptation Self‐evaluation Scale as calibrated using the Beck Depression Inventory

Aim:  The Social Adaptation Self-evaluation Scale (SASS) was developed to assess the social impairment caused by depression. The purposes of this study were to develop a Japanese version of the SASS (SASS-J) and to evaluate its reliability and validity. Methods:  The SASS-J and the 21-item Beck Depression Inventory (BDI) were administered to 322 participants (95 working patients who were working while under treatment for depression, 99 non-working patients who were absent from their work due to depression, and 128 healthy controls). The healthy controls underwent both questionnaires twice, at baseline and 2 weeks later, in order to assess test–retest reliability. Results:  Cronbach's alpha was 0.81. Significance correlations were found between SASS-J scores at baseline and 2 weeks later in healthy controls (R = 0.845, P < 0.001). There were negative correlations between the SASS-J and BDI scores (ρ = –0.683, P < 0.001). Mean SASS-J scores differed significantly among the three groups (working patients: 33.7 ± 7.9; non-working patients: 25.2 ± 7.8; healthy controls: 36.1 ± 6.0 [mean ± SD]). The best compromise between the true positive and the false negative rate in this study was at a cut-off point of 25/26. Conclusion:  SASS-J showed sufficient reliability and validity, and could be considered a suitable instrument to evaluate social functioning in depressive patients.