Methods	RCT
Participants	289 women with CIN I,II,III
Interventions	Laser ablation LLETZ
Outcomes	Residual/recurent disease Primary haemorrhage Duration of pregnancy
Notes	134 allocated to laser ablation. 120 received allocated treatment 155 allocated to LLETZ 151 received allocated treatment
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Yes	“Consecutively numbered, sealed, opaque envelopes were used to allocate women to treatment with loop diathermy excision of the transformation zone or laser vaporisation according to a computer generated randomisation schedule stratified by centre”
Allocation concealment?	Yes	“Consecutively numbered, sealed, opaque envelopes were used”
Blinding? All outcomes	Unclear	Not reported
Incomplete outcome data addressed? All outcomes	Yes	% of women analysed: 285/289 (99%)
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