Fibromyalgia in patients with non-psychotic mental disorders: Prevalence, associated factors and validation of a brief screening instrument.

Background: Fibromyalgia (FM) is a chronic pain syndrome associated with significant distress and numerous unpleasant consequences. Mental health problems in people with FM have been reported in many studies. People with mental disorders are thought to be at higher risk of FM than the general population, but the prevalence has not been established.