Table 1. Numerical Example of direct and indirect standardization.
Hospital A | Hospital B | |||
Urgent | Non-urgent | Urgent | Non-urgent | |
Expected mortality rate | 6% | 2% | 6% | 2% |
Observed mortality rate | 3% | 4% | 3% | 4% |
Case-mix | 1000 | 4000 | 4000 | 1000 |
Indirect standardization | 136 | 61 | ||
Direct standardization | 100 | 100 | ||
Although both hospitals have the same observed mortality hospital A performs worse than hospital B when the mortality rate is adjusted via the indirect standardization method.