Shaw 1990.

Study characteristics
Methods	Trial design: Multi‐centre, placebo‐controlled, randomised trial
Participants	82 women were randomised; 74 were analysed. Mean age: not stated Inclusion criteria: Endometriosis Exclusion criteria: not stated Setting: United Kingdom (2 sites) Timing: not stated
Interventions	Nafarelin 200 mcg BD IN + placebo PO for 6 months (n = 55) versus Danazol 200 mg three times a day PO + placebo IN for 6 months (n = 26)
Outcomes	Improvment of most troublesome symptom: dysmenorrhoea, dyspareunia, pelvic pain, pelvic tenderness and induration combined
Notes	Intention‐to‐treat analysis: not stated Sample size calculation: not stated Funding: not stated Note previous version: Authors contacted but unable to provide further details as trial was almost 20 years old
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Randomized". 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	Low risk	Participants were blinded and received placebo nasal spray or tablets.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Placebo‐controlled study
Incomplete outcome data (attrition bias) All outcomes	Low risk	Details for attrition given: 8 withdrew: Nafarelin = 3 due to side effects, 1 left country, 1 poor compliance  Danazol = 2 due to side effects, 1 poor compliance
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