Headache in the world: public health and research priorities.

Headache disorders are ubiquitous, prevalent and disabling, yet under-recognized, underdiagnosed and undertreated everywhere. A recent WHO survey of headache disorders "illuminates the worldwide neglect of a major public health problem, and reveals the inadequacies of responses to it in countries throughout the world." In this depressing context, the most profitable future for headache research - in the sense of maximizing benefit to people with headache - lies in health services research. This, backed by health economic studies, is likely to show that reallocation of resources towards better healthcare delivery, more effectively using treatments already available, has greater potential to benefit than the search for new drugs. In a world in which the lives of most people with headache are untouched by treatment developments of the last 20 years, there is far greater utility gain from finding ways to reach them than from striving to do a little better in the relatively well-served small minority.