Sommerfleck et al developed a simplified version of the Ankylosing Spondylitis Disease Activity Score, referred to as the SASDAS. The authors are from Instituto de Rehabilitacion Psicofisica in Buenos Aires.
Patient selection: ankylosing spondylitis
Parameters:
(1) patient global assessment as a VAS score on a 0 to 10 cm scale
(2) back pain (from BASDAI) as a VAS score on a 0 to 10 cm scale
(3) peripheral pain and swelling (from BASDAI) as a VAS score on a 0 to 10 cm scale
(4) duration of morning stiffness (from BASDAI) in minutes as 0 to 10 (see below)
(5) ESR in mm in first hour
points for morning stiffness =
= MIN(10,(minutes)/12))
points for ESR =
= MIN(10,((ESR)/10))
SASDAS =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 50
• The higher the score the more active the disease.
Total Score |
Disease Activity |
< 7.9 |
inactive |
7.9 to 13.8 |
moderate |
13.9 to 27.6 |
high |
> 27.6 |
very high |
Performance:
• The sensitivity was 82% and specificity 99% for discriminating inactive from moderate disease activity.
• The sensitivity was 90% and specificity 99% for discriminating moderate from high disease activity.
• The sensitivity was 93% and specificity 100% for discriminating high from very high disease activity.
Specialty: Immunology/Rheumatology