Abstract: We found 21 RCTs including 2482 participants with migraine, and we extracted meta-analytic data from 14 of these studies. The majority of studies recruited participants through advertisements, included participants with migraine according to the International Classification of Headache Disorders (ICHD) criteria and those with and without aura. Most intervention arms were a form of behavioural or cognitive-behavioural therapy. The majority of comparator arms were no treatment, routine care or waiting list. Interventions varied from one 20-minute session to 14 hours of intervention. No study had unequivocally low risk of bias; all had at least one domain at high risk of bias, and 20 had two to five domains at high risk. Reporting of randomisation procedures and allocation concealment were at high or unclear risk of bias. We downgraded the quality of evidence for outcomes to very low, due to very serious limitations in study quality and imprecision. Reporting in trials was poor; we found no preregistrations stipulating the outcomes, or demonstrating equivalent expectations between groups. Few studies reported our outcomes of interest, most only reported outcomes post treatment; follow-up data were sparse. Post-treatment effects We found no evidence of an effect of psychological interventions for migraine frequency in number of migraines or days with migraine (standardised mean difference (SMD) −0.02, 95% confidence interval (CI) −0.17 to 0.13; 4 studies, 681 participants; very low-quality evidence). The responder rate (proportion of participants with migraine frequency reduction of more than 50%) was greater for those who received a psychological intervention compared to control: 101/186 participants (54%) with psychological therapy; 37/152 participants (24%) with control (risk ratio (RR) 2.21, 95% CI 1.63 to 2.98; 4 studies, 338 participants; very low-quality evidence). We found no effect of psychological therapies on migraine intensity (SMD −0.13, 95% CI −0.28 to 0.02; 4 studies, 685 participants). There were no data for migraine duration (hours of migraine per day). There was no effect on migraine medication usage (SMD −0.06, 95% CI −0.35 to 0.24; 2 studies, 483 participants), mood (mean difference (MD) 0.08, 95% CI −0.33 to 0.49; 4 studies, 432 participants), quality of life (SMD −0.02, 95% CI −0.30 to 0.26; 4 studies, 565 participants), or migraine-related disability (SMD −0.67, 95% CI −1.34 to 0.00; 6 studies, 952 participants). The proportion of participants reporting adverse events did not differ between those receiving psychological treatment (9/107; 8%) and control (30/101; 30%) (RR 0.16, 95% CI 0.00 to 7.85; 2 studies, 208 participants). Only two studies reported adverse events and so we were unable to draw any conclusions. We rated evidence from all studies as very low quality. Follow-up Only four studies reported any follow-up data. Follow-ups ranged from four months following intervention to 11 months following intervention. There was no evidence of an effect on any outcomes at follow-up (very low-quality evidence). This review identified 21 studies of psychological interventions for the management of migraine. We did not find evidence that psychological interventions affected migraine frequency, a result based on four studies of primarily brief treatments. Those who received psychological interventions were twice as likely to be classified as responders in the short term, but this was based on very low-quality evidence and there was no evidence of an effect of psychological intervention compared to control at follow-up. There was no evidence of an effect of psychological interventions on medication usage, mood, migraine-related disability or quality of life. There was no evidence of an effect of psychological interventions on migraine frequency in the short-term or long-term. In terms of adverse events, we were unable to draw conclusions as there was insufficient evidence. High and unclear risk of bias in study design and reporting, small numbers of participants, performance and detection bias meant that we rated all evidence as very low quality. Therefore, we conclude that there is an absence of high-quality evidence to determine whether psychological interventions are effective in managing migraine in adults and we are uncertain whether there is any difference between psychological therapies and controls.

Plain-language summary: We searched databases in July 2018 and found 21 studies with 2482 participants. Most studies investigated one of three interventions, namely a form of psychological therapy called cognitive-behaviour therapy (CBT), which teaches skills to change thoughts and behaviours. Skills include coping strategies, or biofeedback or relaxation, which teaches people to reduce their tension either by concentrating on relaxing exercises or through a machine that gives feedback about muscle tension or body temperature. The remaining psychological treatments were examined in single studies; they included writing about emotions and eye movement desensitisation, and reprocessing, which uses eye movements to help people accept their pain and other negative experiences. We were interested in outcomes following treatment and at the longest available follow-up. We found no evidence that psychological treatments resulted in less migraine frequency in the four weeks following treatment. However, we could only include four studies in this analysis that were not high quality. Four studies reported the proportion of people whose migraines reduced in frequency by 50% or more, and in those studies, people who received psychological treatment were twice as likely to respond to treatment (i.e. 50% reduction in migraine frequency) as those in the control group. There was no evidence that psychological treatments affected migraine intensity, medication use for migraine, mood or quality of life. Only two studies assessed adverse events, and so we were unable to draw conclusions. We found very few follow-up data, and no evidence to support or refute any long-term effects of psychological treatment. We rated the quality of the evidence using four levels: very low, low, moderate, or high. High-quality evidence means that we are very confident in the results. Very low-quality evidence means that we are very uncertain about the results. We judged the quality of evidence as very low. There is no evidence that psychological treatments affect the frequency of migraine. More responders (i.e. those reporting a 50% reduction) received psychological treatment than control, but this was based on very low-quality evidence and therefore we are uncertain of this result. In terms of adverse events, we were unable to draw conclusions as there was insufficient evidence. There were very few long-term data available, and no indication that psychological interventions had any long-term effects. Overall there was an absence of high-quality evidence for the effect of psychological treatment on migraines and therefore we are uncertain whether there is any difference between psychological therapies and controls. Funding of high-quality studies is needed and additional studies may change the conclusions of this review.