CHA₂DS₂-VASc refines CHADS₂ by adding age 65–74, vascular disease, and female sex to better identify truly low-risk patients and improve discrimination across the risk spectrum. Large nationwide and cohort validations show CHA₂DS₂-VASc improves classification versus CHADS₂, with higher c-statistics and better identification of patients safe to forgo anticoagulation when scores are 0 in men or 1 in women.

In the Danish nationwide validation, CHA₂DS₂-VASc outperformed CHADS₂ for predicting thromboembolism and more accurately defined low-risk status, with superior risk classification metrics over long-term follow-up. Comparative analyses and reviews from cardiology societies endorse using CHA₂DS₂-VASc for routine risk assessment in AF, reserving anticoagulation for those with elevated scores while avoiding treatment in truly low-risk patients.

External work in Asian and Western populations shows consistent stepwise increases in ischemic stroke with rising CHA₂DS₂-VASc and confirms very low event rates in guideline-defined low-risk groups. U.S. public health resources highlight AF as a major contributor to severe stroke, reinforcing the value of systematic risk stratification and prevention strategies. Overall, CHA₂DS₂-VASc is simple, validated, and widely adopted to support shared decisions about anticoagulation, with periodic reassessment as patients age or develop new comorbid conditions.