Background
migraine
MIGRAINE, MEDICATION OVERUSE HEADACHE, CHRONIC HEADACHE, TENSION TYPE HEADACHE
The Chronic Headache Education and Self-Management Study (CHESS) was a multicentre randomised controlled trial comparing a group education and self-management intervention with a best usual care plus relaxation control for participants living with chronic tension type headaches, chronic migraine with or without medication overuse headache [Evaluation of the principal processes of a complex study helps to explain how an intervention could be optimised or why it may have failed [