The prevalence and clinical features of fibromyalgia in Chinese hospital patients with primary headache: The survey of fibromyalgia comorbid with headache.

The prevalence of fibromyalgia in mainland Chinese patients with primary headache was 6.0%. Fibromyalgia was more common in those with chronic rather than episodic headache. The most common sites of fibromyalgia pain were the neck, shoulders, and back.