ABCD² Score (TIA)
Calculate the standard 0–7 ABCD² score from age, initial blood pressure, clinical features, symptom duration and diabetes, with component-level results and modern triage limitations.
Content updated: View sources
QuickMedCalc is developed and maintained by an independent developer. Medical content is not independently reviewed by a physician.
Formula and medical content are based on the references listed on this page. See sources, About, and Sources and Review Process.
About
Formula
Interpretation
Exact five-component scoring
Age ≥60: 1. Initial SBP ≥140 or DBP ≥90: 1. Unilateral weakness: 2; isolated speech disturbance: 1; other: 0. Duration 10–59 minutes: 1; ≥60 minutes: 2. Diabetes: 1. Weakness takes precedence when speech disturbance is also present.
Historical derivation groups
The 2007 development/validation cohorts reported 2-day estimates of 1.0% for 0–3, 4.1% for 4–5 and 8.1% for 6–7. These are historical cohort observations, not current individualized probabilities.
Diagnosis and mimics
ABCD² cannot diagnose TIA, exclude stroke, or distinguish migraine, seizure, hypoglycemia and other mimics. Ongoing symptoms require acute stroke evaluation. The tissue-based TIA definition requires no acute infarction.
Important risks not included
The score omits MRI DWI infarction, carotid or intracranial stenosis, atrial fibrillation and other cardiac embolic sources, recurrent or crescendo events, anticoagulation, etiology and other imaging findings. A low score excludes none of these.
Disposition and treatment limitations
Do not use ABCD² alone to decide discharge, admission, antiplatelet or dual-antiplatelet therapy. This page performs no medication or treatment algorithm; diagnosis, imaging, bleeding risk, contraindications and the local stroke pathway are required.
Current guideline context
The 2023 AHA scientific statement combines risk tools with neurological, brain/vascular imaging and cardiac assessment [5]. The 2021 ESO guideline opposes prediction tools alone for triage or treatment, and ACEP advises against relying on ABCD² to identify patients safe for emergency discharge. The 2026 AHA/ASA acute ischemic stroke guideline uses ABCD² ≥4 as one criterion in specific early antiplatelet recommendations for selected high-risk TIA pathways, alongside other clinical, timing, imaging, etiology and safety requirements [6, 7]. The formal July 27, 2026 correction was audited as a companion source and does not materially change this bounded ABCD² context. This does not make ABCD² a standalone diagnosis, disposition rule or medication selector. This page calculates the historical five-component score and preserves the original cohort-risk context only; it does not execute a current treatment pathway.
References
- 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. PMID 15993230. DOI 10.1016/S0140-6736(05)66702-5.
- 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. PMID 17258668. DOI 10.1016/S0140-6736(07)60150-0.
- Perry JJ, et al. Prospective validation of the ABCD2 score for patients in the emergency department with transient ischemic attack. CMAJ. 2011;183(10):1137–1145. PMID 21646462. DOI 10.1503/cmaj.101668.
- Wardlaw JM, et al. ABCD2 score and secondary stroke prevention: meta-analysis and effect per 1,000 patients triaged. Neurology. 2015;85(4):373–380. PMID 26136519. DOI 10.1212/WNL.0000000000001780.
- Amin HP, et al. Diagnosis, Workup, Risk Reduction of Transient Ischemic Attack in the Emergency Department Setting. Stroke. 2023;54(3):e109–e121. PMID 36655570. DOI 10.1161/STR.0000000000000418.
- Prabhakaran S, Gonzalez NR, Zachrison KS, et al. 2026 Guideline for the Early Management of Patients With Acute Ischemic Stroke: A Guideline From the American Heart Association/American Stroke Association. Stroke. 2026;57(8):e316–e436. PMID 41582814. DOI 10.1161/STR.0000000000000513.
- Prabhakaran S, Gonzalez NR, Zachrison KS, et al. Correction to: 2026 Guideline for the Early Management of Patients With Acute Ischemic Stroke: A Guideline From the American Heart Association/American Stroke Association. Stroke. 2026;57(8):e461–e467. PMID 42507797. DOI 10.1161/STR.0000000000000530.
- Fonseca AC, et al. European Stroke Organisation guidelines on management of transient ischaemic attack. Eur Stroke J. 2021;6(2):CLXIII–CLXXXVI. PMID 34414299. DOI 10.1177/2396987321992905.
- ACEP Clinical Policies Subcommittee. Clinical Policy: Critical Issues in the Evaluation of Adult Patients With Suspected TIA in the Emergency Department. Ann Emerg Med. 2016;68(3):354–370.e29. PMID 27568419. DOI 10.1016/j.annemergmed.2016.06.048.
- Easton JD, et al. Definition and evaluation of transient ischemic attack. Stroke. 2009;40(6):2276–2293. PMID 19423857. DOI 10.1161/STROKEAHA.108.192218.
FAQ
ABCD² is a five-component 0–7 short-term risk-stratification score used after clinical assessment of suspected TIA. It does not diagnose TIA or provide an individualized probability.
Age 60 or older scores 1; initial systolic blood pressure at least 140 or diastolic at least 90 scores 1; unilateral weakness scores 2 or isolated speech disturbance 1; duration 10–59 minutes scores 1 or at least 60 minutes 2; documented diabetes scores 1.
Use the first documented pressure for the qualifying presentation. The threshold is an OR rule: systolic at least 140 mmHg or diastolic at least 90 mmHg.
Unilateral weakness scores 2 even if speech disturbance is also present. Speech disturbance without unilateral weakness scores 1; they are not added together.
Under 10 minutes scores 0, 10–59 minutes scores 1, and 60 minutes or longer scores 2.
The 2007 development/validation cohorts reported 2-day estimates of 1.0%, 4.1% and 8.1% respectively. These historical cohort figures are not individualized current probabilities.
No. A low score cannot exclude acute infarction, carotid or intracranial stenosis, atrial fibrillation or another high-risk cause.
No. It cannot diagnose TIA or distinguish it from migraine, seizure, hypoglycemia or another mimic; clinical and imaging assessment is required.
No. It cannot independently determine emergency discharge, admission or urgency; neurological, brain/vascular imaging and cardiac assessment remain necessary.
No. A score of 4 or more does not automatically trigger dual antiplatelet therapy. Diagnosis, imaging, bleeding risk, contraindications and the applicable stroke pathway are required.
It excludes MRI DWI infarction, vascular imaging, carotid or intracranial stenosis, atrial fibrillation and other embolic sources, recurrent events, anticoagulation and etiology.
Do not use it to replace acute stroke evaluation for ongoing, recurrent or worsening symptoms, for unassessed self-diagnosis, or automatically in children.
Related Calculators
NIHSS
Calculate the standard adult NIH Stroke Scale from all 15 scored entries, with permitted untestable-item documentation and complete item-level results.
Hunt-Hess
Assign the standard five-grade Hunt–Hess clinical category for aneurysmal subarachnoid hemorrhage from the documented presentation, with exact criteria and neutral limitations.
GCS
Record the standard adult Glasgow Coma Scale eye, verbal, and motor responses, including documented not-testable components without creating a misleading total.
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.