Babjuk 2005.

Study characteristics
Methods	randomized, parallel unblinded single center/Czech Republic
Participants	Study setting primary and recurrent only Ta/T1 Eligibility criteria patients with suspected primary or recurrent superficial BCa planned for TURBT Non‐eligibility criteria surgical or instillation therapy within 3 months Intervention cohort participants recruited: 64 unifocal/multifocal tumors: 15/45 Comparator cohort participants recruited: 64 unifocal/multifocal tumors: 24/38
Interventions	Intervention: WLC + BLC followed by BL‐TURBT Comparator: WLC followed by WL‐TURBT Adjuvant instillation therapy: NA
Outcomes	Outcome(s)* recurrence‐free survival recurrence rate progression rate (to muscle invasive disease) Results median follow‐up: 24 months RFS was 17.1 months in intervention group vs 8.1 months in comparator group RFS rate was 40% in intervention group vs 28% in comparator group
Funding sources	Grant of Czech Health Ministry
Declarations of interest	NA
Contact of study author	Date of contact attempt to first study author: 30 November 2020 Contact status: reply by author; original study data no longer available
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "The patients were randomly assigned to two groups." Comment: method of sequence generation unclear
Allocation concealment (selection bias)	Unclear risk	Quote: "The patients were randomly assigned to two groups." Comment: allocation concealment unclear
Blinding of participants and personnel (performance bias) Surgeon	High risk	Quote: NA Comment: surgeon unblinded
Blinding of participants and personnel (performance bias) Participants/study personnel	Unclear risk	Quote: NA Comment: unclear whether study participants and other study personnel were blinded
Blinding of outcome assessment (detection bias) Subjective outcomes (all outcomes)	Unclear risk	Quote: NA Comment: unclear whether study personnel were blinded
Incomplete outcome data (attrition bias) Oncological outcomes	Low risk	Quote: "six [participants] (two in group A and four in group B) were excluded after histological examination, as in two there was no histological evidence of TCC, in three there was muscle invasion, and in one there was a multiple T1G3 tumour with concomitant carcinoma in situ (CIS) treated with immediate cystectomy." Comment: loss to follow‐up was < 10%, and variation in loss to follow‐up between groups was low
Selective reporting (reporting bias)	Unclear risk	Quote: NA Comment: no protocol available
Other bias	Low risk	Quote: NA Comment: no other bias identified