Validation of the Japanese version of the Roland-Morris Disability Questionnaire.

The study was designed to validate a translated, culturally adapted questionnaire. We examined the reliability, validity, and responsiveness of the Japanese version of the Roland-Morris Questionnaire (RDQ) when assessing disability in Japanese patients with low back pain. The RDQ is a reliable, validated scale used to measure disability caused by low back pain. However, no validated Japanese version of this questionnaire is available. A series of 214 outpatients with low back pain participated in this validation study. The patients were given the RDQ and the SF-36, and assessed their pain and global rating of health. Among them, 57 who were clinically stable were given the RDQ again 2 weeks later. The reliability was examined based on the test-retest method and internal consistency. Sufficient reliability was demonstrated with a Chronbach's. coefficient of 0.85, and the reproducibility for the 30 patients was r = 0.91. The principal component analysis showed unidimensionality. The RDQ score of the 133 patients was significantly improved after treatment. The Japanese version of the RDQ is a useful scale that is easy to use with reliability, validity, and responsiveness when assessing patients with low back pain.