Methods	Multicentre, randomised, double-blind, placebo-controlled, parallel-group. Single dose to treat up to 3 successive attacks Medication administered at the first sign of headache pain Assessments at 1, 2, 3, 4, 6, 8, and 24 hours after dosing Second injection available to participants after 2 h to treat recurrence of headache or if the response to the initial injection had been inadequate Rescue medication (non-ergotamine) was permitted 2 h after the second injection
Participants	Aged 18 to 65, at least 6-month history of migraine (diagnostic criteria equivalent to IHS 1988) without aura Frequency of 1 to 6 attacks per month in the past 12 months, characterised by slow developing headache (the time interval between onset of mild headache and development of moderate or severe headache had to be consistently greater than 1 hour) N = 349 M 62, F 287 (82%) Mean age 40 years 100% without aura
Interventions	Sumatriptan 6 mg, n = 136 Placebo, n = 113
Outcomes	Serious adverse events Withdrawals
Notes	Oxford Quality Score: R1, DB1, W1. Total = 3.
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not reported
Study size	Unclear risk	Treatment groups 50 to 200 participants