The development of a questionnaire to measure the severity of symptoms and the quality of life before and after surgery for stress incontinence

Objectives To develop and validate a short questionnaire recording the severity of symptoms and the quality of life, pre- and post-operatively, in women undergoing surgery for stress incontinence. Design The questionnaire was designed from previously designed questionnaires and pilot studies. In this study, it was tested for validity and reliability using standard psychometric techniques. Data from the questionnaire are reported to a national database, which generates reports for comparison of surgical procedures, departments and surgeons. Setting Tertiary referral urogynaecology units at Baerum and Aker Hospitals, Norway, and 22 Norwegian departments of gynaecology. Population Fifty and 65 women with stress incontinence from Baerum and Aker hospitals, respectively, and 628 women with stress incontinence from 22 Norwegian departments of gynaecology. Methods Stress Incontinence, Urge Incontinence and Quality of Life Indices were constructed. Internal consistency of the indices was measured by Cronbach's alpha and test-retest reliability by Bland-Altman plots. Stress Incontinence Index was tested against stress test and Urge Incontinence Index and Stress Incontinence Index were tested against the 24-hour pad test. Quality of Life Index was tested against a part of the King's College Hospital Quality of Life Questionnaire. Main outcome measures Face and content validity. Missing values of the questionnaire. Reliability and internal consistency. Criterion validity. Results The 628 women completed a mean of 98.2% of all the questions. The content validity was good. The reliability was good in terms of test-retest reliability and internal consistency. The criterion validity of stress and urge incontinence was tested against the stress and 24-hour pad tests. The correlation between the indices and the objective tests was moderate. The correlation between the Quality of Life Index and the physical and social part of the previously validated King's College Hospital questionnaire was good. Conclusions The questionnaire is easy to understand and complete and is a valid and reliable instrument for assessment of the symptoms of incontinence and the quality of life. Pre- and post-operative evaluation of women with stress incontinence was performed in a standardised setting in 22 of the 37 Norwegian departments and the reporting to a national database was successful. Comparison of surgical procedures, departments and surgeons is possible.