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ABCD² Score (TIA) — Free Online Calculator

ABCD² Criteria

ABCD² Score

0

Low risk (~1.0% 2-day stroke risk)

About This Calculator

The ABCD² score is a clinical prediction tool used to estimate the short-term risk of stroke following a transient ischemic attack (TIA). It uses five factors — Age, Blood pressure, Clinical features, Duration, and Diabetes — to stratify patients into low, moderate, and high risk categories. It helps guide decisions about urgent evaluation and hospitalization after TIA.

Formula

ABCD² = Age + BP + Clinical features + Duration + Diabetes
Range: 0 – 7 points

Interpretation

ABCD² ScoreRisk Level2-Day Stroke Risk
0 – 3Low~1.0%
4 – 5Moderate~4.1%
6 – 7High~8.1%

References

  1. Johnston SC, et al. Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. Lancet. 2007;369(9558):283-292.
  2. Rothwell PM, et al. A simple score (ABCD) to identify individuals at high early risk of stroke after transient ischaemic attack. Lancet. 2005;366(9479):29-36.

Frequently Asked Questions

How soon after TIA should the ABCD² score be calculated?

The ABCD² score should be calculated immediately upon presentation. It estimates 2-day, 7-day, and 90-day stroke risk. Even low-risk patients should undergo urgent evaluation including brain imaging and vascular studies, as the score has moderate sensitivity.

Does a low ABCD² score mean I can safely discharge the patient?

Not necessarily. While low-risk patients (0–3) have ~1% 2-day stroke risk, the ABCD² score does not account for etiology. Patients with symptomatic carotid stenosis, atrial fibrillation, or intracranial stenosis may be high risk regardless of their ABCD² score.

Has the ABCD² score been validated in diverse populations?

The ABCD² score has been validated in multiple international cohorts. However, its discriminative ability is moderate (c-statistic ~0.60–0.70), and some guidelines recommend urgent evaluation for all TIA patients regardless of ABCD² score, particularly when rapid workup is available.

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⚠ Medical Disclaimer

This tool is for educational and informational purposes only. It is not intended to replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional for clinical decisions.