Howell 1995.

Study characteristics
Methods	Trial design: Randomised controlled trial
Participants	Participants: 50 women were randomised; 48 completed 24 weeks of treatment and underwent second laparoxcopic assessment. Mean age: Group 1: 29 ± 6 years, group 2: 30 ± 5 years Inclusion criteria: Pelvic pain and a minimum Pelvic Pain Score (defined below) of 3  Regular menstrual cycle (21 to 42 day cycles) Negative cervical smear within the preceding 12 months Use barrier contraception for the duration of the treatment period A minimum revised American Fertility Score (revised AFS) for endometriosis lesions (excluding adhesions) of four was required. Exclusion criteria:  Drugs known to affect bone metabolism in the 6 months preceding the trial Medical conditions known to affect bone mineral density or bone mineral metabolism Setting: United Kingdom Timing: not stated
Interventions	Group 1: 3.6 mg SC depot injection of goserelin every 4 weeks versus Group 2: 3.6 mg SC injection every four weeks and transdermal oestrogen 25 ug daily and 5 mg medroxyprogesterone acetate daily for 20 weeks commencing with the second goserelin depot
Outcomes	Relief of overall pain: relief of symptoms and clinical signs Bone mineral density Adverse effects Endometriosis response Endocrinologic effects Serum lipids and lipoproteins
Notes	Intention‐to‐treat analysis: not stated Sample size calculation: not stated Funding: Study sponsored by Zeneca Pharmaceuticals Note previous version: 20 participants did not complete all the bone mineral density assessments ‐ 2 did not complete treatment and the other 18 did not complete follow‐up.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Were randomised".  No further details of method used to generate the randomisation sequence were provided.
Allocation concealment (selection bias)	Unclear risk	No details of method used to conceal allocation were provided.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Open‐label trial. No further details provided of blinding of participants or personnel
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details provided of blinding of outcome assessment
Incomplete outcome data (attrition bias) All outcomes	High risk	20/48 participants did not complete all the bone mineral density assessments. 2/48 did not complete treatment and the other 18/48 did not complete follow‐up.
Selective reporting (reporting bias)	Low risk	The study protocol was not available but it was clear that the published reports included all expected outcomes, including those that were prespecified.
Other bias	Low risk	No other risk of bias detected