ABCD² Score Calculator

ABCD² Score Calculator for Neurology. Do not turn a low total into reassurance or delayed referral. NICE advises against ABCD2 for risk or referral urgency and recommends specialist assessment within 24 hours: https://www.nice.org.uk/guidance/NG128/chapter/recommendations

For shared guidance on choosing a tool and documenting results, read the clinical calculator workflow.

How this calculator works

Sum five domains, maximum 7. BP contributes once when systolic pressure is >=140 OR diastolic pressure is >=90; weakness and speech points are not added together. Original model: https://pubmed.ncbi.nlm.nih.gov/17258668/

When to use this calculator

A historical risk description after suspected adult TIA, not a stroke diagnostic test. Ongoing symptoms belong in an acute stroke assessment.

Inputs used

  • Adult suspected TIA with symptoms resolved
  • Age in years
  • Initial systolic pressure in mmHg
  • Initial diastolic pressure in mmHg
  • Unilateral weakness, isolated speech disturbance, or other clinical symptoms
  • Episode duration in minutes
  • Established diabetes: present, absent or unassessable

Clinical interpretation

Do not turn a low total into reassurance or delayed referral. NICE advises against ABCD2 for risk or referral urgency and recommends specialist assessment within 24 hours: https://www.nice.org.uk/guidance/NG128/chapter/recommendations

Worked example

At age 60, BP 128/90, isolated speech disturbance lasting 10 minutes, and no diabetes: age 1 + BP 1 + speech 1 + duration 1 = 4. Exactly 60 minutes contributes 2 duration points.

Limitations and safety notes

The score misses important mechanisms and imaging findings. No individual stroke probability, aspirin order, admission decision or discharge clearance is produced.

Frequently asked questions

Must both blood-pressure values be high?

No. Either threshold contributes one point; two elevated values still contribute only one.

References

  • Johnston et al. ABCD2 derivation and validation, Lancet 2007: https://pubmed.ncbi.nlm.nih.gov/17258668/
  • NICE NG128 recommendations; current page reviewed in 2026: https://www.nice.org.uk/guidance/NG128/chapter/recommendations

Editorial review and citation methodology

Maintained by the Quick Medical Calculator Editorial Team. Content record date: September 9, 2026. A content date is not evidence of independent clinical review. Individual clinical sign-off is not recorded on this page.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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