Translation, validation of the EORTC esophageal cancer quality-of-life questionnaire for Japanese with esophageal squamous cell carcinoma: analysis in thoraco-laparoscopic esophagectomy versus open esophagectomy

Objective: The aim of this study is to develop and examine the reliability and validity of the Japanese version of the European Organization for Research and Treatment of Cancer quality-of-life questionnaire-esophageal cancer (OES18) module for its use in Japan.

Methods: We followed a two-phase process to translate the questionnaire, according to the guidelines of the European Organization for Research and Treatment of Cancer OES18. Phase 1: the first intermediary Japanese version was produced according to European Organization for Research and Treatment of Cancer quality-of-life unit translation project guidelines. The second intermediary version was the result of a backward translation project and two peer-to-peer discussion by healthcare professionals. Phase 2: the final Japanese version was produced after focus group discussions with team members and semistructured interviews.

Results: Fifty patients with esophageal squamous cell carcinoma, who had undergone curative thoracic esophagectomy, participated in the study. The Japanese translated version of quality-of-life questionnaire-OES18 yielded cultural adaptation and validation scores whose reliability was confirmed by internal consistency tests. Convergent validity was moderate to high (from r = 0.671-0.903; P < 0.01), whereas discriminant validity was acceptably low. Significant reduction in pain-scale values was noted postoperatively in the thoracoscopic approach when compared with the thoracotomy approach (scale value: 9.62 vs. 12.71; P = 0.04).

Conclusions: We developed the Japanese version of quality-of-life questionnaire-OES18. This module has good psychometric validity and recommended to assess the health-related quality of life in Japanese patients.