Bath Ankylosing Spondylitis Disease Activity Index (BASDAI)

Calculates BASDAI for axial spondyloarthritis disease activity using six questions about fatigue, spinal/peripheral joint pain, localized tenderness, and morning stiffness to guide biologic treatment initiation.

Weight
Height
Clinical Guidance

BMI is a screening measure of body size, not a direct measure of body fat. The standard WHO categories are underweight (<18.5), normal (18.5–24.9), overweight (25–29.9), and obese (≥30).

BMI can overestimate body fat in athletes with high muscle mass and underestimate it in older adults with low muscle mass. Interpret it alongside waist circumference and clinical context rather than as a standalone diagnosis.

⚕ Clinical Disclaimer: These calculators are for educational and reference purposes only. Always verify results with qualified clinical judgment and current clinical guidelines. Do not use as a sole basis for medical decisions.
Advertisement

How It Works

Calculates BASDAI for axial spondyloarthritis disease activity using six questions about fatigue, spinal/peripheral joint pain, localized tenderness, and morning stiffness to guide biologic treatment initiation

Each component has a specific meaning:

  • Six questions about fatigue — The six questions about fatigue recorded for the patient or scenario being assessed.
  • Spinal/peripheral joint pain — The spinal/peripheral joint pain recorded for the patient or scenario being assessed.
  • Localized tenderness — The localized tenderness recorded for the patient or scenario being assessed.
  • Morning stiffness — The morning stiffness recorded for the patient or scenario being assessed.

Note: Interpret the basdai score result against the clinical thresholds and context described above.

How to Use

Enter the six questions about fatigue, spinal/peripheral joint pain, localized tenderness, morning stiffness for the patient or scenario you are assessing. Calculates BASDAI for axial spondyloarthritis disease activity using six questions about fatigue, spinal/peripheral joint pain, localized tenderness, and morning stiffness to guide biologic treatment initiation. Use the basdai score result to inform your clinical assessment.

Frequently Asked Questions