Stănescu 2014.

Study characteristics
Methods	Study design: randomized controlled trial Study grouping: parallel group
Participants	Inclusion criteria: people with one or more suspected non‐muscle invasive bladder cancer of over 3 cm in diameter. Exclusion criteria: people with muscle invasive bladder cancer Number randomized: 260 (130 participants to undergo WLC TURBT and 130 participants to undergo NBC+WLC guided bipolar plasma vaporization) Number analyzed by authors Adverse events: 109 participants to undergo WLC TURBT and 112 participants to undergo NBI‐guided bipolar plasma vaporization 1‐ and 2‐year recurrence: 93 participants who underwent WLC TURBT and 97 participants who underwent NBI + WLC guided bipolar plasma vaporization Baseline characteristics (unclear if reported characteristics were of participants randomized or participants analyzed)  Comparator group, n = unclear  Age, mean (range): 64.8 (33 to 86) Gender‐male, n (%): not reported Tumor focality, n (%): not reported Tumor size: only included participants with tumors > 3 cm in diameter Pathological classification, n (%): not reported Pathological grade, n (%): not reported Intervention group, n = unclear Age, mean (range): 65.2 (32 to 87) Gender‐male, n (%): not reported Tumor focality, n (%): not reported Tumor size: only included participants with tumors > 3 cm in diameter Pathological classification, n (%): not reported Pathological grade, n (%): not reported Subsequent intravesical treatment: In all cases without bladder wall perforations, a single post‐operative mitomycin‐C instillation was performed. In all participants with NMIBT, standard monopolar repeat TUR was performed 4 weeks after the initial procedure followed by a 1‐year bacille Calmette‐Guérin intravesical instillation.
Interventions	Comparator arm: WLC TURBT, followed by a single postoperative instillation with doxorubicin or epirubicin within 24 hours after surgery Intervention arm: NBI + WLC guided bipolar plasma vaporization (Visera video system), followed by a single postoperative instillation with doxorubicin or epirubicin within 24 hours after surgery
Outcomes	Adverse events  Tumor detection rate by pathology Re‐TURBT rate Recurrence rate at 12 months Recurrence rate at 24 months
Funding sources	Not reported
Declarations of interest	Not reported
Notes	Contact with study author Date of contact attempt: 13 January 2021 Contact status: no reply to‐date Time to disease recurrence data found in Geavlete 2012 (Urology) companion paper.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "All participants signed an approved written informed consent form that properly explained the aims, methods, anticipated benefits, potential hazards, and any other aspect of the study relevant to the participant's decision to participate. They were subsequently randomized using sealed envelopes and were unaware of which diagnostic and treatment alternative was applied in each case." Comment: Sealed envelopes were used for sequence generation, which was deemed adequate.
Allocation concealment (selection bias)	Low risk	Quote: "All participants signed an approved written informed consent form that properly explained the aims, methods, anticipated benefits, potential hazards, and any other aspect of the study relevant to the participant's decision to participate. They were subsequently randomized using sealed envelopes and were unaware of which diagnostic and treatment alternative was applied in each case." Comment: There was central randomization with allocation sequence concealment.
Blinding of participants and personnel (performance bias)	High risk	Comment: Personnel could not be blinded due to the nature of the intervention.
Blinding of outcome assessment (detection bias) Subjective outcomes: time to disease recurrence, minor adverse event	High risk	Comment: Authors did not specify how, if any, outcome assessment blinding was achieved. The detection of disease recurrence and minor adverse events would be affected by a lack of blinding of outcome assessors.
Blinding of outcome assessment (detection bias) Objective outcomes: major adverse event	Low risk	Comment: The authors did not specify how, if any, blinding of outcome assessment was conducted. However, we do not expect the lack of blinding to bias the detection or reporting of major adverse events as no clinical judgement was involved.
Incomplete outcome data (attrition bias) Time to disease recurrence	High risk	Comment: Of the 260 participants randomized (130 to the WLC TURBT arm, and 130 to the NBI + WLC TURBT arm), 97 (75%) and 93 (72%) participants of the respective arms completed the follow‐up. The attrition rate was greater than 20% in both arms.
Incomplete outcome data (attrition bias) Major adverse event	High risk	Comment: Of the 260 participants randomized (130 to the WLC TURBT arm, and 130 to the NBI + WLC TURBT arm), 97 (75%) and 93 (72%) participants of the respective arms completed the follow‐up. The attrition rate was greater than 20% in both arms.
Incomplete outcome data (attrition bias) Minor adverse event	High risk	Comment: Of the 260 participants randomized (130 to the WLC TURBT arm, and 130 to the NBI + WLC TURBT arm), 97 (75%) and 93 (72%) participants of the respective arms completed the follow‐up. The attrition rate was greater than 20% in both arms.
Selective reporting (reporting bias)	Unclear risk	Comment: No associated trial registration found.
Other bias	Low risk	Comment: No additional sources of potential bias were identified.

Abbreviations and descriptions: 

CIS/Tis: urothelial carcinoma in situ, “flat tumor”; IQR: interquartile range; NBI: narrow band imaging; SD: standard deviation; pT0: no evidence of primary tumor (pathologically staged); pT1: tumor invades lamina propria (pathologically staged); pTa: noninvasive papillary carcinoma (pathologically staged); TURBT: transurethral resection of bladder tumor; TX: primary tumor cannot be assessed; WLC: white light cystoscopy