Results of pubovaginal sling for stress incontinence: A prospective comparison of 4 instruments for outcome analysis

Purpose: Presently to our knowledge there are no standardized techniques to assess outcomes after surgery for stress incontinence. We performed a prospective blinded study to assess the correlation among physician and patient assessments, and a validated 24-hour pad test and voiding diary. Materials and Methods: A total of 84 women were evaluated before and after pubovaginal sling for stress incontinence with a voiding diary, pad test and symptom questionnaire (patient assessment) administered by a blinded third party. The operating surgeon evaluated the patient using history, physical examination, pad test and voiding diary but was blinded to results of the outcome questionnaire. Preoperative focused neurourological examination and video urodynamics confirmed stress incontinence. Patients were assessed at least 1 year postoperatively, We compared patient assessment (cured, improved, failure) to the outcome of the pad test, voiding diary and physician assessment. The physician and questioner were blinded to each other. We considered patients with a pad test of 0 to 2 ml. as cured, 50% or more volume reduction as improved and less than 50% volume reduction as failure. Postoperative assessment did not differentiate between stress and urge incontinence. The kappa coefficient was used for statistical comparison. Results: Average patient age was 58 years and average followup for the entire group was 4 years. Agreement among the 4 instruments to assess outcome was excellent (k >0.9) with respect to cured/improved versus failure but only good for cured versus improved versus failure (k >0.5). Conclusions: Outcomes following incontinence surgery may vary depending on how the analysis was performed, patient selection, definition of success and so forth. Our results indicate that a pad test and voiding diary are reliable and should be part of the normal followup after pubovaginal sling for sphincteric incontinence. When these tests are used in conjunction with defined parameters of success, there is excellent agreement with patient feelings in regard to success or failure of surgery. Nevertheless, these instruments and methods are imperfect at best.