Vercellini 1999.

Methods	Location: Italy No. of centres: 19 Recruitment period: February 1992 to June 1994
Participants	Inclusion criteria: pre‐menopausal, endometriosis score >/= 4 points, chronic pelvic pain Exclusion criteria: NS No. randomised: 269 No. analysed: 210
Interventions	Post‐surgical medical therapy Gr A (n= 133): goserelin SC 3.6 mg every 4 weeks x 6 months Gr B (n=134): no treatment
Outcomes	Pain recurrence Pregnancy rates
Notes	Power calculation: Yes Funding: Zeneca Pharmaceuticals provided drugs and financial support
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"randomised in a proportion of 1:1 ... in accordance with a computer‐generated randomisation sequence"
Allocation concealment (selection bias)	Low risk	centralised randomisation, allocation obtained by phone call
Blinding (performance bias and detection bias) All outcomes	High risk	not mentioned, no placebo
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	269 patients randomised, 2 excluded because case record forms not completed, 26 & 31patients (22%) withdrew from treatment and control groups respectively for reasons other than symptom recurrence or were excluded due to major protocol violations. Reasons for exclusion similar in each group‐ may have introduced bias
Selective reporting (reporting bias)	Low risk	important outcomes of recurrence, dysmenorrhoea and pregnancy reported
Other bias	Low risk	groups appear comparable at baseline