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Illustration of the effect of collapsing exposure categories
| X1=1 | X1=2 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Diseased | Not diseased | Total | RR | Diseased | Not diseased | Total | RR | ||
| 1 | 50 | 650 | 700 | 1.00 | 1 | 25 | 275 | 300 | 1.00 |
| 2 | 50 | 250 | 300 | 2.33 | 2 | 125 | 575 | 700 | 2.14 |
The table gives the observed situation after collapsing
