Ankylosing Spondylitis is one of the Inflammatory Diseases of Immune Dysregulation.
The gold standard for measuring and evaluating disease activity in Ankylosing Spondylitis is the BASDAI, or the Bath Ankylosing Spondylitis Disease Activity Index. The BASDAI is the result of the work of a research team consisting of rheumatologists, physiotherapists, and research associates with a special interest in AS who developed the index in Bath, England. The BASDAI consists of a one through 10 scale (one being no problem and 10 being the worst problem) which is used to answer 6 questions pertaining to the 5 major symptoms of AS:
Fatigue
Spinal pain
Joint pain / swelling
Areas of localized tenderness (also called enthesitis, or inflammation of tendons and ligaments)
Morning stiffness duration
Morning stiffness severity
When evaluated using strict clinical paramaters, the BASDAI was validated:
BASDAI is a quick and simple index (taking between 30 secs and 2 mins to complete)
BASDAI demonstrated statistically significant (p<0.001) reliability.
BASDAI encorporates a reasonable scale. The individual symptoms and the index as a whole demonstrated good score distribution, using 95% of the scale.
BASDAI demonstrates a sensitivity to change within a short period of time. Following a 3 week physiotherapy course, the BASDAI showed a significant (p=0.009) 16.4% score improvement.