Methods	RCT
Participants	300 women with CIN 1,2,3 Women with adequate colposcopy, no evidence of invasion
Interventions	Laser conisation LLETZ
Outcomes	Duration of treatment Patient subjective assessment of pain (none/minimal, moderate, severe) Peri-operative blood loss (difference in weight of blood stained/dry swabs) Secondary haemorrhage Presence of thermal artifact not permitting evaluation of resection margins Dysmenorrhoea Residual disease at 3-12 months
Notes	150 women randomised to laser conisation, 150 to loop excision Intra-cervical 6mls Citanest (0.5% prilocaine with octapressin) used pre-operatively
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	Not reported, merely states that, “women were randomized to receive treatment either by loop diathermy excision or laser excisional conization”
Allocation concealment?	Yes	“The women were randomized to receive treatment either by loop diathermy excision or laser excisional conization by drawing from a box of sealed, opaque, mixed envelopes of the same color and size, each of which contained the name of one of the procedures”
Blinding? All outcomes	Unclear	Not reported
Incomplete outcome data addressed? All outcomes	Yes	% of women analysed: 295/300 (98%) or secondary haemorrhage, dysmenorrhoea and residual disease: “All patients except two in group 1 and three in group 2 attended at least one follow-up clinic. Attempts to contact these patients by telephone, letter, or through their general practitioners failed. ” 100% of women were assessed for all other outcomes as they could be measured during or immediately after surgery
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