NCT01211145.

Study characteristics
Methods	Randomized, double‐blind, placebo‐controlled, parallel group trial of zolmitriptan nasal spray
Participants	Participants from 74 study sites worldwide were adolescents 12‐17 years of age, diagnosed with migraine per IHS 1988 or revised IHS criteria (Winner 1995) and a history of at least 2 migraine attacks per month. Lack of response to single‐blind placebo run‐in period was also required. Randomized (N = 798); did not receive study drug (N = 141); analyzed (N = 584)
Interventions	Zolmitriptan 0.5, 2.5, 5 mg nasal spray
Outcomes	Pain‐free at 2 h Headache relief (defined as decreased from severe or moderate to mild or none) at 2 h Use of rescue medication during the first 24 h Presense of nausea or vomiting at 2 h Other reported outcomes: Presence of photophobia, phonophobia, nausea, or vomiting at 0.25, 1, 3, 4, and 24 h Headache relief (defined as decreased from severe or moderate to mild or none and no use of rescue medication) at 0.25, 1, 3, 4, and 24 h Pain‐free at 0.25, 1, 3, 4, and 24 h
Headache severity scale	4‐point scale (none, mild, moderate, severe)
Funding source	AstraZeneca
Publication	Clinical trial registry
Notes	At the interim futility analysis, the zolmitriptan 0.5 and 2.5 mg groups were declared futile, allocation discontinued, and not included in the efficacy analysis
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "were randomized into the study to obtain 800 evaluable patients" Comment: no description of randomization procedures provided
Allocation concealment (selection bias)	Unclear risk	Comment: no information provided
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Comment: study is described as blinded but no information provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "Of the 798 patients, 82.3% (657/798 patients) received study drug, 90.4% (721/798 patients) completed the study and 9.5% (76/798 patients) discontinued from the study. . . All patients received their assigned treatment. . . Overall, the most common reason for study discontinuation was eligibility criteria not fulfilled (6.6%, 53/798 patients). No patients discontinued due to AEs."
Selective reporting (reporting bias)	Unclear risk	Comment: a clinical study report synopsis was reported with limited data