Table 2.
Event Rates and c‐Statistics Comparing the CHADS2 and CHA2DS2‐VASc Scores at 1‐, 5‐, and 10‐Year Follow‐upa
| Scale | Event Rates per 100 Person‐Years | c‐Statistic (95% CI)b | ||
|---|---|---|---|---|
| Low Risk (Score 0) | Intermediate Risk (Score 1) | High Risk (Score >1 ) | ||
| At 1 year | ||||
| CHADS2 | 1.7 | 4.8 | 12 | 0.72 (0.69–0.75) |
| CHA2DS2‐VASc | 0.78 | 2.0 | 8.8 | 0.85 (0.83–0.87) |
| At 5 years | ||||
| CHADS2 | 1.3 | 3.7 | 8.3 | 0.80 (0.78–0.81) |
| CHA2DS2‐VASc | 0.69 | 1.5 | 6.0 | 0.88 (0.87–0.89) |
| At 10 years | ||||
| CHADS2 | 1.2 | 3.6 | 8.0 | 0.81 (0.80–0.83) |
| CHA2DS2‐VASc | 0.66 | 1.5 | 5.7 | 0.89 (0.88–0.90) |
Abbreviations: CHADS2, Congestive heart failure, Hypertension, Age ≥75 years, Diabetes mellitus, and previous thromboembolism (double points); CHA2DS2‐VASc, Congestive heart failure, Hypertension, Age ≥75 years (double points), Diabetes mellitus, previous thromboembolism (double points), Vascular disease, age 65–74 years, and female gender; CI, confidence interval.
a
From Olesen et al.21
b
Based on Cox regression models using 3 risk groups and with covariates analyzed as categorical variables.