For example, in 2004/5, two Australian health surveys investigated rates of long-term
circulatory system health problems (e.g. heart disease) in the general Australian population, and specifically in the
Indigenous Australian population. In each age category over age 24, Indigenous Australians had markedly higher rates of circulatory disease than the general population: 5% vs 2% in age group 25–34, 12% vs 4% in age group 35–44, 22% vs 14% in age group 45–54, and 42% vs 33% in age group 55+.
[1]
However, overall, these surveys estimated that 12% of all Indigenous Australians had long-term circulatory problems
[1] compared to 18% of the overall Australian population.
[2]
To understand this apparent contradiction, note that the indigenous population is comparatively young (median age 21 years, compared to 37 for non-indigenous) due to relatively high birth and death rates.
[3] Because of this, Indigenous figures are dominated by the younger age groups, which have lower rates of circulatory disease; this masks the fact that their risk at each age is higher than for non-Indigenous peers of the same age.