Randomised or quasi-randomised controlled trials (RCTs) that compared inside-out versus outside-in TO-TVT in adult women with SUI and urethral hyper-mobility and/or intrinsic sphincter deficiency or mixed incontinence with predominant SUI were included. Both clinical and urodynamic diagnoses of SUI were eligible. Cohort studies that compared the two procedures directly were included.
The primary outcome was clinical cure or improvement of incontinence (either patient-reported or objectively assessed). Other outcomes included surgical outcomes, peri-operative and postoperative complications, impact on women's quality of life and sexual function.
Included studies were conducted in women with both SUI and mixed urinary incontinence (MUI) with or without prior incontinence surgery. Mean age was 51.5 years for the inside-out group and 55.5 years for the outside-in group. Mean BMI (body mass index) was 27.23 for the inside-out group and 28.15 for the outside-in group. Follow-up periods ranged from 12 weeks to 12 months in the RCTs and was either 12 months or a mean of 38 months in the cohort studies. Definitions of objective cure included the one-hour standard International Continence Society (ICS) pad test, urodynamic studies and the cough stress test. Other reported outcomes included patient satisfaction (for example, measured on a visual analogue scale), voiding difficulty, pain at discharge and at follow-up and quality of life questionnaires.
The authors did not clearly state how many reviewers performed study selection. It appeared that one author screened titles and abstracts for potentially relevant studies and these were then screened by a second author.