Methods	RCT
Participants	All women over 20 years of age who required a LLETZ for suspected CIN on colposcopy Mean age in the trial was 34.4 years (SD=9.2 years)
Interventions	Pure cut: the standard Valleylab force 2 electrosurgical generator (Valleylab, CO) was set to 90W Blend 1: both cut and coagulation were set to 60W. The diathermy setting blend 1 is a combination of 50% cutting waveform and 50% coagulating waveform Prior to the procedure, the extent of the lesion was determined with 3% acetic acid and the cervix was injected with 4-6 ml of 3% prilocaine hydrochloride with felypressin. The size of the disposable loop was selected by the operator and performed in the standard way
Outcomes	Residual disease (follow-up smear 6 months after LLETZ procedure) Grading and depth of thermal artefact
Notes	Residual disease was assessed at 6 months follow up based on a smear result Mean depth of thermal artefact at the epithelial margin was 0.292 mm in the blend group and 0.270 mm in the cut group (P=0.237). It was not possible to obtain a SD so this could not be displayed on a forest plot
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	”Randomization was performed using sequential sealed envelopes. No blocking or stratification was carried out“
Allocation concealment?	Unclear	”Randomization was performed using sequential sealed envelopes“. It was unclear whether these were opaque sealed envelopes
Blinding? All outcomes	Unclear	Not reported
Incomplete outcome data addressed? All outcomes	Yes	”Three eligible women declined to take part in the trial and three were not randomized for unknown reasons. The remaining 49 women were randomized to either the cut or the blend setting for the LLETZ procedure Of the 55 eligible patients % of women analysed: 49/55 (89%) Of the 49 patients who were randomised % of women analysed: 49/49 (100%)
Free of selective reporting?	Unclear	Insufficient information to permit judgement
Free of other bias?	Unclear	Insufficient information to assess whether an important risk of bias exists