Correlation between tender points and the fibromyalgia impact questionnaire

Objectives: To investigate a possible correlation between the number of tender points [TePs] and the myalgic score versus the Activities of Daily Living [ADL] items and the pain visual analog scale [VAS] of the Fibromyalgia Impact Questionnaire [FIQ]. Methods: Consecutive patients with fibromyalgia were included [N = 221; 213 females, eight males, mean age 46 years]. The diagnosis was established using the criteria of the American College of Rheumatology: widespread pain for at least three months and pain on palpation in at least 11 out of 18 specified TeP locations. A 4-point (0-3) scale of pain severity was used. Each patient was evaluated by the number of TePs and by a myalgic score expressed by the summation of the pain severity score multiplied by the respective number of TePs. Before the clinical examination the patients filled in the FIQ. The first 10 subitems of the FIQ, measuring physical functioning [FIQ-ADL], were used. Results: The FIQ-ADL. was correlated to the following parameters: pain on the VAS [r(s) = 0.46; P < 0.001], the myalgic score [r(s) = 0.30; P < 0.001], and the number of TePs [r(s) = 0.20; P = 0.003]. Some correlation between the myalgic score and pain on the VAS was seen [r(s) 0.15; P = 0.004]. We found no correlation between the number of TePs and pain on the VAS. Conclusion: As an indicator of disability the myalgic score appears to be preferable to the number of TePs. Self-reported pain is correlated to the physical function as expressed by the FIQ-ADL.