DAS 28 score (with thanks to NRAS)

The DAS28 is a measure of disease activity in rheumatoid arthritis (RA).

DAS stands for “disease activity score” and the number 28 refers to the joints that are examined in this assessment.

This is not the only scoring system used in RA but is the one most commonly used in everyday clinical practice and most clinical trials looking at RA outcomes have used DAS28 as part of their measurements.

Disease Activity Score

National Rheumatoid Arthritis Society

DAS Score

The “ DAS28” is a composite score derived from 4 of these measures. The standard version uses “ESR” as the marker of inflammation but there is a version that uses “CRP”.

To calculate your DAS28 your rheumatologist or specialist nurse will:-

  • Count the number of swollen joints (out of the 28)
  • Count the number of tender joints (out of the 28)
  • Take blood to measure the Erythrocyte Sedimentation rare (ESR) or the C-reactive protein (CRP)
  • Ask you (the patient) to make a “global assessment of health” (indicated by marking a 10cm line between very good and very bad)

These results are then fed into a complex mathematical formula to produce the overall disease activity score.

DAS28 higher than 5.1           indicates severe disease activity

DAS28 between 3.2-5.1         indicates moderate disease activity

DAS28 between 2.6-3.2         indicates low disease activity


At present DAS28 scoring is essential for screening for NHS funded anti TNF therapy and patient must have a DAS28 >5.1 on at least 2 occasions (after failure of other treatments)

DAS score chart
This shows the joints that are used to calculate DAS28 and the way it will be entered when you attend your clinic appointment.
DAS pdf

In Clyde Hospital patients with RA will have their DAS score measured at most clinic visits and in our Early Arthritis clinics we use a DAS28 guided scoring scale to guide treatment.

Please ask the doctor or nurse if you want to know what your DAS28 score is and how it is being used to guide your treatment.

We will hopefully soon  be able to ask patients to complete their own global assessment and tender joint counts while waiting in the clinic.

NRAS have produced an excellent booklet,  

“Know Your Disease Activity Score and stay one step ahead of your PA”

if you want more information and they have lots of information on their website.


NRAS have now developed on app for patients to measure their own DAS28 score – please ask your rheumatology doctor or nurse if you want to have your measurement included in our assessments