DAS28 Rheumatoid Arthritis Score

Summary

The DAS28 (Disease Activity Score in 28 joints) is a composite measure used to describe rheumatoid arthritis disease activity. This calculator implements the validated four-variable ESR and CRP formulas using tender and swollen 28-joint counts, an inflammatory marker, and a 0–100 mm patient global assessment. A score is one part of a clinician’s longitudinal assessment and is not a stand-alone treatment instruction.

How it works

1. Select the variant: DAS28-ESR (uses erythrocyte sedimentation rate) or DAS28-CRP (uses C-reactive protein).
2. Enter the 28 Tender Joint Count (TJC28) — the number of joints that are painful on pressure or passive movement.
3. Enter the 28 Swollen Joint Count (SJC28) — the number of joints with soft-tissue swelling.
4. Enter the ESR (mm/hr) or CRP (mg/L) laboratory value for the inflammatory marker.
5. Enter the Patient Global Assessment (PGA) on a 0–100 mm visual analog scale (0 = no activity, 100 = maximum activity).
6. Click Calculate to see the DAS28 score and EULAR disease activity category.

Use cases

• Monitor disease activity at each clinic visit for patients with rheumatoid arthritis.
• Record whether a calculated score falls below the conventional DAS28 remission threshold.
• Assess response to biologic or DMARD therapy using EULAR response criteria.
• Document disease burden for insurance authorization of biologic agents.
• Compare pre- and post-treatment scores to quantify therapeutic benefit.
• Support clinical trial enrollment and outcome reporting.
• Educate patients on their current disease activity level in a standardized way.
• Differentiate conventional low, moderate, and high activity bands for discussion with a clinician.

Frequently Asked Questions