Table 5.
Performance of risk stratification schemes to predict ischaemic stroke in patients aged ≥75 with atrial fibrillation who were not taking warfarin
| Risk scheme | C statistic* | Hazard ratio (95% CI) | P value |
|---|---|---|---|
| Stratum | |||
| CHADS2 original | 0.55 (0.49 to 0.61) | 1.61 (0.93 to 2.80) | 0.09 |
| CHADS2 revised | 0.61 (0.57 to 0.66) | 3.29 (1.49 to 7.28) | 0.003 |
| Framingham: | |||
| Moderate v low | 0.59 (0.55 to 0.65) | 4.99 (1.18 to 21.10) | 0.03 |
| High v moderate | 1.17 (0.68 to 2.03) | 0.56 | |
| NICE | 0.59 (0.54 to 0.63) | 2.93 (1.25 to 6.68) | 0.01 |
| ACC/AHA/ESC† | 0.61 (0.57 to 0.66) | 3.29 (1.49 to 7.28) | 0.003 |
| ACCP: | |||
| Moderate v low | 0.60 (0.54 to 0.65) | 0.75 (0.09 to 5.89) | 0.78 |
| High v moderate | 2.61 (1.27 to 5.35) | 0.009 | |
| Scores | |||
| CHADS2 index | 0.61 (0.54 to 0.68) | 1.35 (1.07 to 1.70)‡ | 0.01 |
| Rietbrock modified | 0.62 (0.59 to 0.68) | 1.17 (1.06 to 1.29)‡ | 0.001 |
| CHA2DS2-VASc | 0.60 (0.55 to 0.68) | 1.21 (0.99 to 1.47)‡ | 0.06 |
*Assesses discrimination where 0.5 is non-informative test.
†Equal to CHADS2 revised because of unavailability of risk factors left ventricular function, mitral stenosis, and prosthetic heart valve in BAFTA data.
‡Per unit increase in score.