SPARTACUS: underdiagnosis of chronic daily headache in primary care.

Despite the burden of chronic daily headache (CDH), general practitioners' (GPs) ability to recognize it is unknown. This work is a sub-study of a population-based study investigating GPs' knowledge on their CDH patients. Patients diagnosed with CDH through the screening questionnaire were interviewed by their GPs who indicated if subjects were known as patients suffering from CDH with medication overuse (MO), CDH without MO, episodic headache (EH) or non-headache sufferers. Our study showed that 64.37 % of CDH sufferers are misdiagnosed by their GPs. However, overusers are better known to GPs.