Methods	RCT
Participants	105 women with histologically verified CIN.
Interventions	Needle excision of the transformation zone (NETZ), in which a new, specially designed diathermy needle is used Large loop excision (LLETZ) Cold knife
Outcomes	Mean operating time including anaesthesia Free resection margins Residual disease Mean postoperative duration of vaginal discharge Success rate after single treatment
Notes	Follow-up time is three years; all patients were evaluated at 3, 6, 9, 12, 18, 24 and 36 months after surgery Mean operating time including anaesthesia (NETZ 7.4 minutes, LLETZ 8.6 minutes, cold knife 17.7 minutes, P<0.05) Conversion to general anaesthesia (NETZ 11%, LLETZ 22%, cold knife 37%, P=0.04) Free resection margins (NETZ 85%, LLETZ 37%, cold knife 68%, P<0.05) Residual disease (NETZ 2%, LLETZ 28%, cold knife 14%, P<0.05) Mean post-operative duration of vaginal discharge (NETZ 9 days, LLETZ 12 days, cold knife, 13 days, P<0.05) Success rate after single treatment (NETZ, 97.1%, cold knife 85.7%, LLETZ 71.4%)
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	Not reported
Allocation concealment?	Unclear	Not reported
Blinding? All outcomes	Unclear	Not reported
Incomplete outcome data addressed? All outcomes	Yes	% of women analysed: 105/105 (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