Table 1.
Hypothetical distribution of subjects according to the predictors and outcome incidence
| High incidence (50%) |
Intermediate incidence (20%) |
Low incidence (5%) |
|||||
|---|---|---|---|---|---|---|---|
| Independent Variable |
Cases (n = 500) |
Non-cases (n = 500) |
Cases (n = 200) |
Non-cases (n = 800) |
Cases (n = 50) |
Non-cases (n = 950) |
Total (n = 1000) |
| Predictor A | |||||||
| positive | 409 | 191 | 161 | 439 | 45 | 555 | 600 |
| negative | 91 | 309 | 39 | 361 | 5 | 395 | 400 |
| Predictor B | |||||||
| positive | 398 | 102 | 159 | 341 | 36 | 464 | 500 |
| negative | 102 | 398 | 41 | 459 | 14 | 486 | 500 |
| Predictor C | |||||||
| positive | 227 | 173 | 84 | 316 | 23 | 377 | 400 |
| negative | 273 | 327 | 116 | 484 | 27 | 573 | 600 |