EBMcalc Logo
  CHADS2 Score for Stroke Risk in Atrial Fibrillation (CHADS[2])


Diagnosed heart failure, past or current (1 point)

Hypertension treated or untreated (1 point)

Age ≥75 years (1 point)

Diabetes Mellitus (1 point)

Secondary prevention in patients with prior ischemic stroke, TIA or thromboembolism (2 points)

Important: Inputs must be complete to perform calculation.

Total Criteria Point Count:
Include literature references: Yes   No

  Stroke Risk per 100 Person Years/Warfarin Rx Interpretation

0 Points: 0.25 ON Rx; 0.49 NO Rx
1 Point: 0.72 ON Rx; 1.52 NO Rx
2 Points: 1.27 ON Rx; 2.50 No Rx
3 Points: 2.20 ON Rx; 5.27 NO Rx
4 Points: 2.35 ON Rx; 6.02 NO Rx
5 to 6 Points: 4.60 ON Rx; 6.88 NO Rx


  1. Gage BF, Waterman AD, Shannon W, et al. Validation of clinical classification schemes for predicting stroke: results from the National Registry of Atrial Fibrillation. JAMA. 2001 Jun 13;285(22):2864-70. PubMed ID: 11401607 PubMed Logo
  2. Go AS, Hylek EM, Chang Y, et al. Anticoagulation therapy for stroke prevention in atrial fibrillation: how well do randomized trials translate into clinical practice? JAMA. 2003 Nov 26;290(20):2685-92. PubMed ID: 14645310 PubMed Logo
  3. EBMcalc CrossRef: Atrial Fibrillation CHA(2)DS(2)-VASc Score for Stroke Risk
  4. Cairns JA. ACP journal club. CHA2DS2-VASc had better discrimination than CHADS2 for predicting risk for thromboembolism in atrial fibrillation. Ann Intern Med. 2011 May 17;154(10):JC5-13. doi: 10.1059/0003-4819-154-10-201105170-02013. PubMed ID: 21576531 PubMed Logo
  5. Olesen JB, Lip GY, Hansen ML, et al. Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study. BMJ. 2011 Jan 31;342:d124. doi: 10.1136/bmj.d124. PubMed ID: 21282258 PubMed Logo
  6. Wild D. ACP Journal Club. CHADS2 score predicted bleeding and death in atrial fibrillation treated with anticoagulants. Ann Intern Med. 2012 Apr 17;156(8):JC4-13. doi: 10.1059/0003-4819-156-8-201204170-02013. PubMed ID: 22508753 PubMed Logo
  7. Oldgren J, Alings M, Darius H, et al., RE-LY Investigators. Risks for stroke, bleeding, and death in patients with atrial fibrillation receiving dabigatran or warfarin in relation to the CHADS2 score: a subgroup analysis of the RE-LY trial. Ann Intern Med. 2011 Nov 15;155(10):660-7, W204. doi: 10.1059/0003-4819-155-10-201111150-00004. PubMed ID: 22084332 PubMed Logo


Associated ICD10-CM Codes
   I67.9Cerebrovascular disease, unspecified
   I48.91Unspecified atrial fibrillation

Associated ICD9-CM Codes
   427.31Atrial fibrillation
   437.9Cerebrovasc disease nos


Legal Notices and Disclaimer

All information contained in and produced by the EBMcalc system is provided for educational purposes only. This information should not be used for the diagnosis or treatment of any health problem or disease. THIS INFORMATION IS NOT INTENDED TO REPLACE CLINICAL JUDGMENT OR GUIDE INDIVIDUAL PATIENT CARE IN ANY MANNER. Click here for full notice and disclaimer.
EBMcalc is Copyright © 1998-2023 Foundation Internet    [Build 271986 v23.4]