The German linguistic validation of the Wisconsin Stone Quality of Life questionnaire (WisQoL).

WisQoL (Wisconsin Stone Quality of Life questionnaire) is a disease specific, health related quality of life measure designed for patients who form kidney stones. The goal of this study was to develop and validate a German version of WisQoL.

The German version of the WisQoL was developed following a standardized multistep process. Patients were recruited prior to stone treatment, and completed the questionnaire as well as the SF-36v2 (36-Item Short Form Health Survey). This was repeated 1, 3, and 6 months after stone surgery. Scores of the 28 questionnaire items were summarized into sum scores for four domains and a total score. The psychometric properties of the questionnaire were statistically analyzed.

The German WisQoL demonstrated excellent internal consistency (Cronbach's α > 0.90 for all domains at all visits). All inter-domain associations were positive. The test-retest reliability for patients with unchanged self-reported health state was considered satisfactory (Spearman's rho for total score 0.70 [95% CI 0.55 to - 0.80]). The German WisQoL demonstrated good convergent validity with the validated SF-36v2 (correlation between corresponding items 0.44 to 0.64). All domain scores showed significant sensitivity to change induced by stone treatment (p ≤ 0.05). Total WisQoL scores generally improved during the first 3 months following stone treatment, and remained stable thereafter.

The German WisQoL proved to be a reliable and robust instrument to evaluate health related quality of life measures of kidney stone patients in the clinical setting. It is expected to be of use for further research in patients with kidney stones.

World journal of urology. 2020 Aug 12 [Epub ahead of print]

Martin Gottstein, Manolis Pratsinis, Sabine Güsewell, Patrick Betschart, Dominik Abt, Thomas Knoll

Department of Urology, Kliniken Sindelfingen-Böblingen, Arthur-Gruber-Str. 70, 71065, Sindelfingen, Germany. ., Department of Urology, Cantonal Hospital St. Gallen, Rorschacherstrasse 95, 9007, St. Gallen, Switzerland., Clinical Trials Unit, Cantonal Hospital St. Gallen, Rorschacherstrasse 95, 9007, St. Gallen, Switzerland., Department of Urology, Kliniken Sindelfingen-Böblingen, Arthur-Gruber-Str. 70, 71065, Sindelfingen, Germany.