Primary fibromyalgia syndrome: a critical evaluation of recent criteria developments.

Although nonspecific musculoskeletal aching of nonarticular origin has been described in European literature since the 17th century under such names as muscular rheumatism, the fibrositis syndrome with generalized musculoskeletal aches or stiffness, fatigue, poor sleep, and multiple tender points as a characteristic rheumatologic entity was not described until the 1960s. Smythe first suggested criteria for this condition based on clinical experience in the 1970s. However, the first data-based criteria of "fibrositis" (appropriately called fibromyalgia) was not published until 1981. Since then other criteria have been published, and in 1989 criteria studies on fibromyalgia with appropriate design and controls were reported. This article critically evaluates current criteria developments in fibromyalgia.