What is the BASDAI used for?

The BASDAI measures disease activity in ankylosing spondylitis and axial spondyloarthritis. It asks patients to rate fatigue, spinal pain, peripheral joint symptoms, localized tenderness, and morning stiffness over the past week. Clinicians use the resulting 0 to 10 score to gauge how active the condition is and to guide clinical decision-making over time.

How many questions are on the BASDAI?

The BASDAI has six questions. Four ask about fatigue, spinal pain, peripheral joint pain and swelling, and areas of localized tenderness. The remaining two ask about the severity and duration of morning stiffness. Each question is answered on a 0 to 10 scale reflecting the past week of symptoms.

How is the BASDAI scored?

Each of the six items is rated from 0 to 10. The two morning stiffness items are averaged into a single value, which is then combined with the other four items and divided by five. The final score ranges from 0 to 10, with higher numbers indicating more active disease.

What BASDAI score indicates active disease?

A score of 4 or higher is the widely recognized threshold for active disease and suboptimal control. Many guidelines and biologic eligibility criteria use this cutoff when deciding whether to consider further assessment or escalate care. Scores below 4 generally suggest lower disease activity that can be monitored over time.

How often should the BASDAI be repeated?

There is no fixed interval, but the BASDAI is most useful when repeated at regular visits so scores can be compared over time. Many rheumatology practices administer it at each follow-up or when treatment changes, using the trend to judge whether disease activity is improving, stable, or worsening.

Can patients complete the BASDAI at home?

Yes. The BASDAI is patient-reported and takes only a few minutes, so it works well when completed before an appointment. With Zentake, patients answer on any device from home, the score calculates automatically on submit, and results are ready for the clinician to review before the visit.

BASDAI Ankylosing Spondylitis Index | Template & auto-scoring

The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) is a six-item, patient-reported questionnaire that measures the severity of disease activity in people with ankylosing spondylitis and axial spondyloarthritis. It captures fatigue, spinal pain, peripheral joint symptoms, areas of localized tenderness, and morning stiffness, producing a single score from 0 to 10 that reflects how active the condition feels.

Why healthcare providers use the BASDAI

Quantifies disease activity. It turns subjective symptoms into a single 0 to 10 number that guides clinical decision-making.
Supports treatment decisions. A score of 4 or higher signals active disease and helps identify patients who may need further assessment or a change in management.
Tracks response over time. Repeat administration shows whether symptoms are improving, stable, or worsening.
Fast to complete. Patients answer six questions in a few minutes without using clinician time.
Widely recognized. The index is embedded in spondyloarthritis guidelines and biologic eligibility criteria across many health systems.

Which settings use the BASDAI?

Rheumatology clinics. The primary setting for monitoring ankylosing spondylitis and axial spondyloarthritis.
Primary care. Helps identify active disease and supports referral decisions.
Physical therapy and rehabilitation. Tracks symptom burden alongside functional measures.
Clinical research. A standard endpoint in spondyloarthritis trials and registries.

What does the BASDAI measure?

The BASDAI asks patients to rate their experience over the past week across the core symptoms of active spondyloarthritis. Each response uses a 0 to 10 scale, and the six answers combine into one overall activity score. The domains cover:

Fatigue. Overall tiredness related to the condition.
Spinal and axial pain. Pain in the neck, back, and hips.
Peripheral joint symptoms. Pain and swelling in joints other than the spine.
Enthesitis and localized tenderness. Discomfort in areas that are tender to touch or pressure.
Morning stiffness. Both the severity and the duration of stiffness after waking.

Scoring the BASDAI

Number of items. Six questions.
Per-item scale. Each item is rated 0 to 10, originally on a 10 cm visual analog scale and now often on a 0 to 10 numeric rating scale.
Total score range. 0 to 10.
Score direction. Higher scores indicate greater disease activity.

Scoring averages the two morning stiffness items, then combines that value with the other four items and divides by five, keeping the final result on the same 0 to 10 scale. The BASDAI reflects how the patient feels and does not measure structural damage or inflammation directly, so interpret it alongside clinical examination, imaging, and laboratory findings rather than in isolation.

A score of 4 or higher is the widely used threshold for active disease and is often applied when considering whether to escalate care. It functions as a single recognized cutoff rather than a set of validated severity bands, so the table below reflects only that threshold.

Score	Interpretation	Suggested next step
Below 4	Lower disease activity	Monitor and reassess periodically
4 or higher	Active disease, suboptimal control	Consider further assessment

Best practices for administration

Use a consistent recall window. Ask patients to rate the past week each time so scores stay comparable.
Administer before the visit. Completing it at home gives an unhurried baseline for discussion.
Repeat at regular intervals. Compare scores across visits to judge treatment response.
Pair with function measures. Use it alongside a functional index for a fuller clinical picture.
Confirm the scale format. Make sure patients understand the 0 to 10 rating for every item.

How Zentake helps with the BASDAI

Automatic scoring. Zentake totals the six items on submit, so there is no hand-tallying.
Longitudinal tracking. Re-send the questionnaire on a schedule and view change over time.
Before the visit. Patients complete the BASDAI from home on any device, and rheumatology practices have scores ready before the appointment.
HIPAA compliant. Data is encrypted, with a signed BAA on every plan.

References

The BASDAI was developed and validated by Garrett and colleagues: Garrett S, Jenkinson T, Kennedy LG, et al. A new approach to defining disease status in ankylosing spondylitis: the Bath Ankylosing Spondylitis Disease Activity Index. J Rheumatol. 1994;21(12):2286-2291.

The score of 4 or higher as a marker of active disease is reflected in international spondyloarthritis management recommendations and biologic eligibility criteria, including ASAS and EULAR guidance.

Last updated: August 2026

BASDAI Ankylosing Spondylitis Index