Validation study of the Japanese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26 for patients with testicular cancer.

To validate the Japanese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26 in Japanese-speaking testicular cancer survivors.

A total of 200 testicular cancer survivors were recruited at eight high-volume institutions in Japan. The participants completed the Japanese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 and the International Index of Erectile Function 15 questionnaires. A total of 40 participants completed a retest of the questionnaires 2 weeks after the first response. The psychometric properties of the Japanese version including test-retest reliability, internal consistency and concurrent validity were evaluated.

The mean age at response was 43 years (range 22-74 years), and the mean period after treatment was 77 months (range 0-416 months). The response rate for each item, except sexual function, was high, and the percentage of missing values was less than 3.5%. For test-retest reliability, seven of 12 scales met the criteria (intraclass correlation 0.70-0.86). For internal consistency, four of seven scales met the criteria (Cronbach's alpha 0.62-0.91). For concurrent validity, treatment side effects of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26 were related to some domains of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30. The sex-related subscales of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26 were moderately correlated with some International Index of Erectile Function 15 domains.

The psychometric properties of the Japanese version are equivalent to the properties of the original European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26. The Japanese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Testicular Cancer 26 questionnaire is a useful tool to assess the health-related quality of life of testicular cancer patients.

International journal of urology : official journal of the Japanese Urological Association. 2020 Nov 10 [Epub ahead of print]

Shinichi Yamashita, Yoshimi Suzukamo, Kenichi Kakimoto, Motohide Uemura, Takeshi Kishida, Koji Kawai, Terukazu Nakamura, Takayuki Goto, Takahiro Osawa, Shigeyuki Yamada, Kazuo Nishimura, Norio Nonomura, Hiroyuki Nishiyama, Takumi Shiraishi, Osamu Ukimura, Osamu Ogawa, Nobuo Shinohara, Akihiro Ito, Yoichi Arai

Department of, Departments of, Urology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan., Department of, Physical Medicine and Rehabilitation, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan., Department of Urology, Osaka International Cancer Institute, Osaka, Osaka, Japan., Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan., Department of Urology, Kanagawa Cancer Center, Yokohama, Kanagawa, Japan., Department of Urology, University of Tsukuba, Tsukuba, Ibaraki, Japan., Department of Urology, Kyoto Prefectural University of Medicine, Kyoto, Kyoto, Japan., Department of Urology, Graduate School of Medicine and Faculty of Medicine Kyoto University, Kyoto, Kyoto, Japan., Department of Urology, Graduate School of Medicine, Hokkaido University, Sapporo, Hokkaido, Japan.