Outcomes following sling surgery: importance of definition of success.

PURPOSE: The assessment of incontinence therapies is complicated by the diverse outcomes instruments and definitions of success used by investigators. We defined this effect by using varied definitions of success to perform outcomes analysis following sling placement.
MATERIALS AND METHODS: A retrospective review of patients undergoing SPARC (314) and autologous rectus pubovaginal sling (127) placement was performed, with 204 patients with the SPARC and 67 with pubovaginal sling completing questionnaire surveillance with the minimum 12-month followup. Outcomes were assessed using a questionnaire comprising validated incontinence questionnaires (Urogenital Distress Inventory and Incontinence Impact Questionnaire) and additional items addressing satisfaction. Success rates were compared using alternate definitions of success across all outcomes measures (eg dry rate, pad rate, percent improvement, degree of satisfaction).
RESULTS: Wide variations in outcomes were seen depending on the definition used for success (SPARC success range 33% to 87%, pubovaginal sling 40% to 79%). Total absence of leakage was the strictest definition of success while continued use of 1 to 3 liners was associated with the highest success rates. In addition, 74% of patients with SPARC placement and 66% with the pubovaginal sling reported willingness to undergo sling surgery again despite the treatment failing to meet the criteria for success under multiple definitions. Finally, the individual sling type (SPARC vs pubovaginal) associated with the superior success rate varied with the definition of success. However, these differences failed to achieve statistical significance.
CONCLUSIONS: Our data suggest that success rates following sling placement are significantly affected by the definition of success. Investigation to define standardized outcomes measures following incontinence surgery is of great importance to the urological community.