Gladstone, Jonathan P.

Objectives To survey experts in Headache Medicine on their opinions regarding appropriate non‐inferiority margins for outcomes commonly used in migraine research. Methods Members of the American Headache Society and the Canadian Headache Society were invited to participate in the Non‐Inferiority Margins in Migraine Research (NIMM) survey. Adult and child neurologists with expertise in Headache Medicine were eligible to participate. The survey had a multiple choice format and comprised questions on respondent characteristics, eligibility, as well as expert opinion on non‐inferiority margins for outcomes commonly used in trials of both prophylactic and acute interventions for migraine. Results Ninety‐nine eligible respondents completed the survey. Most respondents were adult neurologists (84.9%) and 74% reported practicing in the USA. The following were the most commonly selected non‐inferiority margins: (1) change in monthly migraine attacks comparing baseline to the treatment period: 1 attack (39.4% selecting), (2) change in monthly migraine days comparing baseline to the treatment period: 1 day (44.4%), (3) change in average migraine intensity on a 4‐point scale comparing baseline to the treatment period: 1.0 (31.3%), (4) percentage of participants who are pain‐free 2 hours after the intervention: 5% (41.4%), (5) percentage of participants who have a migraine recurrence within 48 hours of treatment: 5% (42.4%), and (6) percentage of participants with sustained pain freedom: 5% (42.4%). Conclusions The results of the NIMM survey describe the opinions of a group of experts on appropriate non‐inferiority margins for outcomes commonly used in migraine clinical trials. There was significant variability in responses and lack of consensus on the choice of non‐inferiority margins. The survey did not incorporate the patient perspective and was not validated prior to distribution. Further work in this area is required in order to explore how to incorporate clinical considerations into the selection of non‐inferiority margins for migraine research.

Background There is a considerable amount of practice variation in managing migraines in emergency settings, and evidence-based therapies are often not used first line. Methods A peer-reviewed search of databases (MEDLINE, Embase, CENTRAL) was carried out to identify randomized and quasi-randomized controlled trials of interventions for acute pain relief in adults presenting with migraine to emergency settings. Where possible, data were pooled into meta-analyses. Results Two independent reviewers screened 831 titles and abstracts for eligibility. Three independent reviewers subsequently evaluated 120 full text articles for inclusion, of which 44 were included. Individual studies were then assigned a US Preventive Services Task Force quality rating. The GRADE scheme was used to assign a level of evidence and recommendation strength for each intervention. Interpretation We strongly recommend the use of prochlorperazine based on a high level of evidence, lysine acetylsalicylic acid, metoclopramide and sumatriptan, based on a moderate level of evidence, and ketorolac, based on a low level of evidence. We weakly recommend the use of chlorpromazine based on a moderate level of evidence, and ergotamine, dihydroergotamine, lidocaine intranasal and meperidine, based on a low level of evidence. We found evidence to recommend strongly against the use of dexamethasone, based on a moderate level of evidence, and granisetron, haloperidol and trimethobenzamide based on a low level of evidence. Based on moderate-quality evidence, we recommend weakly against the use of acetaminophen and magnesium sulfate. Based on low-quality evidence, we recommend weakly against the use of diclofenac, droperidol, lidocaine intravenous, lysine clonixinate, morphine, propofol, sodium valproate and tramadol.