Reliability and Validity of the DSM-5 Level 1 Cross-Cutting Symptom Measure in Japan: Insights into General and...

The dimensional approach to psychiatric symptoms, including the general psychopathology factor (p-factor), has gained increasing attention for its potential to elucidate pathophysiology and inform treatment. However, comprehensive assessment of transdiagnostic psychiatric symptoms remains particularly challenging, especially in Japan. The DSM-5 Level 1 Cross-Cutting Symptom Measure (DSM-XC) was developed to capture a broad spectrum of symptoms across disorders, yet its validity in assessing both specific symptoms and the p-factor remains underexplored. This study examined the reliability and validity of the DSM-XC in a general population sample in Japan. The results demonstrated that the total DSM-XC score exhibited high internal consistency, test-retest reliability, and convergent validity with self-reported psychiatric measures. However, item-level analysis revealed that several items had low test-retest reliability. Moreover, factor analysis indicated that the DSM-XC primarily captures internalizing symptoms rather than general psychopathology. These findings suggest that while the DSM-XC may serve as an indirect indicator of the p-factor, its ability to directly measure the p-factor itself and assess specific symptoms requires further scrutiny. Although the DSM-XC provides a convenient tool for partly evaluating general and specific symptoms, its limitations underscore the need for further refinement to achieve a more comprehensive assessment of psychopathology.