Validating the Japanese version of the Gastrointestinal Quality of Life Index (GIQLI) questionnaire

Aim To validate a Japanese version of the Gastrointestinal Quality of Life Index (GIQLI) in patients with symptomatic gallstone disease. Methods We investigated responsiveness, reliability, and convergent validity of the translated GIQLI in patients who underwent elective laparoscopic cholecystectomy. Questionnaire scores were compared with the Gastrointestinal Symptom Rating Scale (GSRS) to verify convergent validity. Results There were 120 patients originally enrolled in the study; three were excluded after their surgery as they no longer met the inclusion criteria. Questionnaires were collected from the remaining 117 patients (100% response rate). At 2 weeks post-surgery, total GIQLI score increased significantly from pre-surgery levels, suggesting high responsiveness. Cronbach's alpha ranged from 0.901 to 0.934 for the total score, while a comparison of scores at 2 vs 6 weeks post-surgery yielded an intraclass correlation coefficient of 0.843; thus, the Japanese version of the questionnaire was reliable. Correlations with GSRS ranged between -0.459 and -0.679, indicating fair to good convergent validity. Conclusion The Japanese GIQLI had high responsiveness and reliability to assess how surgery for symptomatic gallstone disease influenced patient quality of life.