Example of distortion in aggregated versus disaggregated results.Annual death rates per 1,000 population, by age, Baltimore city, 1965.

RaceAll

agesAge < 1 yr

1-4 yrs 5-17 18-44 45-64 65+

White 14.3 23.9 0.7 0.4 2.5 15.2 69.3

Black 10.2 31.3 1.6 0.6 4.8 22.6 75.9

1. Note that whites have a higher overall

mortality rate

3. The paradox arises because of the much higher mortality rates in the 65+ age-group, and because many fewer blacks reach this age, so contribute fewer cases overall. The All Ages data should have been age-standardized.

2. Yet in each subgroup, whites

have a lower mortality rate