Validation of the Chinese version of the Pelvic Organ Prolapse Symptom Score (POP-SS)

Objective: The objective of the present study was to translate the Pelvic Organ Prolapse Symptom Score (POP-SS) into Chinese and validate it in a population of Chinese women. Methods: The POP-SS questionnaire was translated into simplified Chinese language following an intercultural adaptation procedure. One hundred forty-six patients who met the inclusion criteria were recruited. Among the enrolled patients, 63 underwent surgery for POP and 50 underwent pessary management. They completed the questionnaires at baseline (T1), 1 to 2 weeks later (T2), and 3 months after intervention (T3). Evaluation for psychometric properties was conducted following with the COnsensus-based Standards for the selection of health Measurement INstruments checklist, including internal consistency, test-retest reliability, measurement error, content validity, criterion validity, construct validity, responsiveness, and interpretability. Results: The POP-SS was successfully translated into a Chinese version and achieved good content validity. Internal consistency (Cronbach's alpha = 0.796) was good, and test-retest reliability was excellent (intraclass correlation coefficients = 0.98; P < 0.001). The construct validity was verified by factor analysis and consistent with the theoretical structure of the original questionnaire. The POP-SS score was also significantly correlated with Pelvic Floor Distress Inventory-20 (Spearman's correlation coefficient = 0.89, P < 0.001). The confirmatory factor analysis identified two factors: physical symptoms and evacuation symptoms. The mean changes among the participants in very much better (9.80 +/- 5.36) and much better (5.67 +/- 2.99) groups were larger than those among the participants in the no change group (0.43 +/- 2.07). The effect size responsiveness parameter in the much better group (>0.80) was larger than that in the no change group (<0.20). The values of the minimal important change for surgery and pessary groups were both larger than the smallest detectable change, indicating sufficient responsiveness. Conclusions: The Chinese version of POP-SS is a reliable and valid instrument and has good sensitivity to change in the population studied.