Lord 2006.

Methods	RCT comparing TVT with SPARC sling
Participants	301 women Inclusion criteria: women presenting with SUI whether or not they had had previous incontinence or other pelvic surgery, or both Exclusion criteria: < 18 years old; pregnant; had a major voiding dysfunction specified as an abnormal flow (i.e. maximum urinary flow rate < 10 ml/s) or residual urinary volume of > 150 ml 254 women had UDS and USI diagnosed MUI: 47 women
Interventions	Group A: TVT (n = 147) Group B: SPARC (n = 154)
Outcomes	Primary outcome: bladder perforation Secondary outcomes: blood loss voiding difficulty urgency cure of SUI symptoms at 6 weeks after surgery The subjective assessments of cure were the participants' reported use of protection, their perceptions of the severity of their SUI symptoms and a scale of improvement (1 to 100). The objective definition of cure was the observed absence of urinary leakage when the participant coughed while supine and with a comfortably full bladder Follow‐up was 6 weeks
Notes	The women and the outcome assessors were blinded, but no clear description was provided for how this was achieved
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were stratified based on previous UI surgery (yes, no) and the experience of the surgeon (consultant, registrar) and allocated to either TVT or SPARC using computer‐generated random numbers. The biostatistician generated the random allocations, which were sealed in opaque, sequentially numbered envelopes. The surgeons recruited participants and accessed the allocations by a telephone call to a third party. Varying block sizes of 4, 6 and 8 were used within each stratum to preclude prediction of allocation by the surgeons
Allocation concealment (selection bias)	Low risk	Concealed
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "The analyst was unaware of the treatment allocation, but it was obviously not possible to ensure that the surgeons were unaware of treatment, although the patients were unable to detect, from their incisions, which sling they had received"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The analyst was unaware of the treatment allocation, but it was obviously not possible to ensure that the surgeons were unaware of treatment, although the patients were unable to detect, from their incisions, which sling they had received"
Incomplete outcome data (attrition bias) All outcomes	Low risk	No differential loss to follow‐up or differential attrition