Validation of the Turkish version of the Wisconsin stone-quality of life questionnaire

Özet

Objective: We validated the Turkish version of the Wisconsin Stone-Quality of Life (WISQoL) questionnaire for male and female patients with kidney stones.Material and methods: The Turkish version of the WISQoL questionnaire was developed following a wellestablished multistep process. A total of 84 patients with kidney stones completed the Turkish WISQoL questionnaire, including the other validated questionnaires as The Short Form Health Survey (SF-36 v2) and Beck'sDepression Inventory. Patients completed questionnaires before percutaneous nephrolithotomy (PNL) surgeryas well as 2–4 weeks after surgery. Reliability was evaluated by internal consistency (tested by Cronbach’s alfa)and test-retest reliability between week 2 and 4 (tested by Spearman correlation). Domain structures were examined by interdomain correlations using Spearman correlation coefficient. Convergent validity was assessed bycorrelating the scores of general health domain to the SF-36 v2, and the scores of emotional impact domain tothe Beck's Depression Inventory questionnaire. Sensitivity to change was assessed by comparing scores beforeand after PNL surgery with the Wilcoxon signed rank test. Discriminant validity was evaluated by comparingthe results of patients 2 and 4 weeks after surgery with Wilcoxon-rank sum tests.Results: The Turkish version of the WISQoL demonstrates good internal consistency (Cronbach’s α=0.72-0.78) and test–retest reliability (p>0.05). Inter-domain associations within the WISQOL showed a substantial correlation between various WISQoL domains, indicating a high conceptual relationship between thedomains. Also, the Turkish version of the WISQoL showed convergent validity with the correspondingvalidated questionnaires (Spearman’s rho correlation coefficient=0.44-0.78). All domains of the WISQoLshowed significant sensitivity to change (p≤0.001).Conclusion: The Turkish version of the WISQoL is a generally reliable instrument that can be self-administered by Turkish patients with kidney stones in clinical and research settings. Further clinical studies inTurkish settings would be useful to provide powerful data on sensitivity to change.