ABCD² Score

TIA — 2-day stroke risk

Age 60 or older

BP ≥ 140/90 mmHg at assessment

Diabetes

Clinical features of the TIA

Unilateral weakness

Speech disturbance without weakness

Other symptoms

Symptom duration

60 minutes or more

10–59 minutes

Under 10 minutes

Evidence

Original publication

Johnston SC, Rothwell PM, Nguyen-Huynh MN, et al. Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack. Derived the ABCD² score; 2-day stroke risk ~1.0% (0–3), ~4.1% (4–5), ~8.1% (6–7).

The Lancet, 2007

Open source

Validation

Giles MF, Rothwell PM. Systematic review and pooled analysis of published and unpublished validations of the ABCD and ABCD2 transient ischemic attack risk scores.

Stroke, 2010

Open source

Last reviewed: 2026-09

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