Fibromyalgia syndrome (FMS) is conceptualized as a chronic disorder characterized by widespread and persistent non-inflammatory musculoskeletal pain. Concomitant symptoms usually include fatigue, insomnia, morning stiffness, depression, anxiety, and cognitive problems (forgetfulness, concentration difficulties, mental slowness, memory and attention problems, etc.). Furthermore, the majority of FMS patients usually show predominantly negative affect, including neuroticism, alexithymia, and catastrophizing and impaired health-related quality of life. Continue reading “1990 Criteria of ACR for the Classification of Fibromyalgia”