Psychometric properties of the pelvic organ prolapse symptom score

Objective To assess the internal consistency, construct validity and sensitivity to change of a pelvic organ prolapse symptom score (POP‐SS). Design Analysis of data from three prolapse studies, including symptomatic and asymptomatic women who completed the POP‐SS. Setting (1) A community setting in New Zealand, (2) two gynaecology outpatient departments in Scotland and (3) a gynaecological surgery department in Scotland. Population or sample (1) Participants from a survey of postnatal women at 12‐year follow up, invited to complete a prolapse questionnaire and have prolapse assessment, (2) new gynaecology outpatients presenting with prolapse symptoms, randomised to pelvic floor muscle training (PFMT) or control and (3) women having anterior and/or posterior prolapse surgery, randomised to mesh insert or no mesh. Method Data were analysed to assess internal consistency, construct validity and sensitivity to change of the POP‐SS. Main outcome measures Cronbach’s alpha, significance of differences in POP‐SS scores between studies and significance of difference in POP‐SS scores pre‐ to post‐intervention. Results For internal consistency, Cronbach’s alpha ranged from 0.723 to 0.828. Women having surgery had higher POP‐SS scores than those having conservative management (mean difference 5.0, 95% CI 3.1–6.9), who in turn had higher scores than the asymptomatic women (mean difference 5.9, 95% CI 4.4–7.4). Significant differences in POP‐SS score were detected after surgery and PFMT. The improvement due to surgery was significantly greater than that associated with PFMT ( z =−3.006, P = 0.003). Conclusion The POP‐SS has good internal consistency and construct validity and is sensitive to change.