Abstract Background The Quick Inventory of Depressive Symptomatology (QIDS) is a useful, validated measure of depressive symptoms that covers the DSM-IV diagnostic criteria for major depressive disorder. The Japanese translation of the QIDS (QIDS-J) has been published, but its psychometric properties have not been validated in large samples. Methods This study aimed to examine the psychometric properties of the QIDS-J using secondary analysis data from a Japanese clinical study of internet-based cognitive-behavioral therapy that includes 1, 187 participants (698 males, 489 females; mean age: 43. 46 ± 9. 85). First, a cross-sectional survey examined descriptive statistics, factor structure, measurement/structural invariance, internal consistency, construct validity, and age and gender differences in measurement scores. Subsequently, a short-term longitudinal and cross-sectional survey was conducted to evaluate test–retest reliability. Results Explanatory and confirmatory factor analyses revealed a one-factor structure that demonstrated good internal consistency and test–retest reliability, as well as partially verified concurrent and construct validity. Conclusions These findings indicate that the QIDS-J has robust psychometric properties and can assess depressive symptoms across nine DSM-IV criterion domains. Trial registration University Hospital Medical Information Network Clinical Trials Registry (UMINCTR) UMIN000019228 (Registration Date October 4, 2015) https: //www. center6. umin. ac. jp/cgiopenbin/ctrₑ/ctrᵥiew. cgi? recptno=R000022220.
Kashimura et al. (Tue,) studied this question.