The number of swollen or tender lower limb joints and the Disease Activity Score-28 joints (DAS-28) were used to assess disease activity. DAS-28 was calculated from the number of swollen and tender joints (28), visual analogue scale for the patient assessment of global health, and erythrocyte sedimentation rate (Smolen et al., 1995). The number of swollen and tender joints was assessed by an experienced rheumatologist, which also applied the visual analogue scale. Erythrocyte sedimentation rate was assessed in the same laboratory for all subjects.
Smolen, J., Breedveld, F., Eberl, G., Jones, I., Leeming, M., Wylie, G., & Kirkpatrick, J. (1995). Validity and reliability of the twenty-eight-joint count for the assessement of rheumatoid arthritis activity. Arthritis and Rheumatism, 38(1), 38–43.