Evaluation of outcomes of Urethral Stricture Surgery: psychometric validation of a Polish language version of the Patient-Reported Outcome Measure for urethral stricture surgery

Introduction The aim of this study is to validate the Polish version of the Urethral Stricture Surgery – Patient-Reported Outcome Measure (USS-PROM) by evaluating its psychometric properties. Material and methods Patients with urethral stricture scheduled for urethroplasty between 2014 and 2018 were prospectively enrolled. The results of the USS-PROM were obtained before the operation, and during follow-up visits. The original USS-PROM was translated into Polish and re-translated into English in accordance with the guidelines by Dawson et al. regarding the adaptation process. Psychometric assessment included internal consistency, test-retest reliability, criterion validity and responsiveness. Results One hundred twelve patients were included. 54 patients completed the USS-PROM both before and 3 months after the surgery and 39 of them completed the questionnaire 6 months after the surgery to evaluate the test-retest reliability. Cronbach's α for internal consistency of the lower urinary tract symptoms (LUTS) domain score was 0.87. The test-retest intraclass correlation coefficient was 0.82. Spearman's coefficients showed no correlation between USS-PROM's result and maximal urinary flow (Qmax) result before the surgery (rs = 0.13; p >0.05) and a positive correlation between USS-PROM's result and Qmax result at follow up: 3 months after (rs =- 0.56; p <0.05), 6 months after (rs -0.64; p <0.05), and 12 months after (rs = -0.85; p <0.05). There were statistically significant strong and positive correlations between LUTS score and International Prostate Symptom Score (IPSS). Responsiveness of the test was confirmed with non-parametric Friedman's analysis of variance (ANOVA) with Kendall's coefficient of concordance (χ2 ANOVA = 8.95, p = 0.03). Conclusions The Polish version of the USS-PROM questionnaire has appropriate psychometric properties and can be used in the assessment of patients with urethral stricture undergoing urethroplasty.