Fibromyalgia: Classification

Criteria for the clinical diagnosis of fibromyalgia syndrome (FMS).

American College of Rheumatology (ACR) 1990 Classification Criteria. Modified ACR 2010preliminary diagnostic criteria.
Obligatory main symptom CWP (chronic widespread pain) according to ACR 1990 criteria.

  • > 3 months of existing pain in:
    • Axial skeleton (cervical spine (C-spine) or anterior thorax/chest or thoracic spine (C-spine) or lumbar spine, lumbar spine); and
    • Right half of the body and left half of the body and
    • Above the waist and below the waist
  • Regional pain index ≥ 7/19 pain locations on the regional pain scale.
Obligatory other symptoms/signs
  • Increased tenderness of at least 11 of 18 tender points.
  • Symptom severity score ≥ 5 *
Exclusion diagnostics
  • None
  • Exclusion of a physical disease that adequately explains the typical symptom pattern.

* Symptom severity score: sum of fatigue, nonrestorative sleep, cognitive problems (each 0 = absent to 3 = extremely pronounced); headache, abdominal pain, depression (each 0 = absent, 1 = present) (range of sum score: 0-12).