Methods	Multicentre, R, DB, PC, parallel-group Single attack treated with a single dose of study medication. Medication taken when pain was moderate or severe. Rescue medication after 2 h if necessary Assessments at 0, 0.5, 1, 1.5, 2, 3, 4, 5, 6 h
Participants	Episodic migraine ± aura (IHS 2004). Age ≥ 18 years. History of 0.5 to 6 attacks/month in past year and previous treatment with OTC medication. Untreated severity ≥ moderate. Excluded: require bedrest for > 50%, or vomiting with > 20% of attacks N = 346 M 58, F 288 Mean age 39 years 22% with aura
Interventions	Paracetamol 1000 mg, n = 177 Placebo, n = 169 Prophylactic medication continued unchanged
Outcomes	Pain-free at 2 h Headache relief at 1 h and 2 h Relief of nausea, photophobia, phonophobia, functional disability Use of rescue medication Adverse events Withdrawals
Notes	Oxford Quality Score: R2, DB2, W1. Total = 5
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Yes	“computer-generated randomization code”
Allocation concealment?	Yes	“blister cards with winged 2-piece code label including treatment assignment according to sponsor-generated randomization code”
Blinding? All outcomes	Yes	“tablets identical in shape, size and color”