DAS28 Calculator (ESR/CRP)
Calculate Disease Activity Score in 28 joints for rheumatoid arthritis follow-up. Choose ESR or CRP method, enter values, and get an instant interpretation.
What is DAS28?
DAS28 (Disease Activity Score using 28 joint counts) is a widely used composite index for monitoring rheumatoid arthritis (RA) activity over time. It combines objective inflammatory markers with clinical joint findings and a patient-reported health score. The result is a single number that helps clinicians track progress and support treat-to-target decisions.
Why this “das28 calculator sanofi” page?
This page provides an easy educational calculator experience for users searching the phrase “das28 calculator sanofi.” It is a practical reference tool for understanding score mechanics. It is not an official brand page, product label, or substitute for physician judgment.
Inputs used in the calculator
Core clinical measures
- Tender Joint Count (TJC28): number of tender joints out of 28 assessed joints.
- Swollen Joint Count (SJC28): number of swollen joints out of the same 28-joint set.
- Patient Global Health (GH): usually a visual analog scale from 0 to 100 mm.
Inflammation marker options
- ESR version: uses erythrocyte sedimentation rate (mm/hr).
- CRP version: uses C-reactive protein (mg/L).
Formula reference
DAS28-ESR = 0.56 × √(TJC28) + 0.28 × √(SJC28) + 0.70 × ln(ESR) + 0.014 × GH
DAS28-CRP = 0.56 × √(TJC28) + 0.28 × √(SJC28) + 0.36 × ln(CRP + 1) + 0.014 × GH + 0.96
How to interpret DAS28
| DAS28 score | Activity level | Typical interpretation |
|---|---|---|
| < 2.6 | Remission | Very low/controlled disease activity |
| 2.6 to 3.2 | Low activity | Generally acceptable control in many patients |
| > 3.2 to 5.1 | Moderate activity | Disease remains active, treatment review often needed |
| > 5.1 | High activity | Substantial inflammation and symptom burden likely |
Clinical context and practical use
DAS28 is most useful when tracked serially, not as a one-time isolated number. Rheumatology teams often use the trend to evaluate treatment response, flare status, and whether current therapy should be maintained, intensified, or adjusted. Pairing the score with imaging, physical exam, and patient goals gives a more complete view of disease control.
Good practice tips
- Use the same method (ESR or CRP) consistently when possible.
- Document date, medication status, and recent infections that may affect biomarkers.
- Compare with prior visits to identify direction of change.
- Interpret alongside morning stiffness, function, pain, and imaging findings.
Limitations to remember
- DAS28 includes 28 joints and may underrepresent disease in feet/ankles.
- Inflammatory markers may be altered by non-RA conditions.
- Pain amplification and comorbidities can influence patient global scoring.
- Thresholds support decisions but should not replace individualized clinical judgment.
FAQ
Is DAS28-CRP the same as DAS28-ESR?
No. They are related but not interchangeable formulas. Always note which version is used when documenting or comparing over time.
Can I use this tool for diagnosis?
No. DAS28 is for monitoring disease activity after diagnosis and in specialist care pathways. Diagnosis of rheumatoid arthritis requires a full clinical workup.
What if the number seems inconsistent with symptoms?
Discuss with your rheumatology clinician. A full assessment can clarify whether inflammation, pain sensitization, structural damage, or another condition is contributing to symptoms.
Medical disclaimer: This calculator is for educational and informational use only. It does not provide medical advice, diagnosis, or treatment.