US racial disparity: how do we compare?
There’s a depressing chart at Fusion, originally from the Economist, that shows international comparisons for infant mortality, homicide, life expectancy, and imprisonment, with White America and Black America broken out as if they were separate countries.
Originally, I was just going to link to the chart, but I thought I should look at how Māori/Pākehā disparities compare. European-ancestry New Zealanders and Māori make up roughly the same proportions of the NZ population as self-identified White and Black do in the US. The comparison is depressing, but also interesting: showing how ratios and differences give you different results.
First, infant mortality. Felix Salmon writes
A look at infant mortality, a key indicator of development, is just as grim. Iceland has 1.6 deaths per 1,000 births; South Korea has 3.2. “White America” is pretty bad — by developed-country standards — with 5.1 deaths per 1,000 births. But “Black America,” again, is much, much worse: at 11.2 deaths per 1,000 births, it’s worse than Romania or China.
According to the Ministry of Health, Māori infant mortality was 7.7/1000 in 2011 compared to 3.7/1000 for non-Māori, non-Pacific. According to StatsNZ, the rate for Māori was lower in 2012 (the numbers don’t quite match: different definitions or provisional data). So, the Māori/Pakeha ratio is similar to the Black/White ratio in the US, but the difference is quite a bit smaller here.
Incarceration rates show a similar pattern. In the US, the rate is 2207/100k for Blacks and 380/100k for Whites. In New Zealand, the rates are (about) 700/100k for Māori and 100/100k for European-ancestry. The NZ figures include people on remand; I don’t know if the US figures do. The ratio is a bit lower in New Zealand, but the difference is dramatically lower.
Homicide rates are harder to compare, because New Zealand only started collecting ethnicity of victims last year, and because NZ.Stat will only show you one month of data at a time. However, it looks as though the ratio is a lot less than the nearly 9 in the US. More importantly, the overall rate is much lower here: our rate is 0.9 per 100k, the overall US rate is 4.5 per 100k.
If the Māori/Pākehā disparities are slightly less serious than US Black/White disparities as ratios but much less serious as differences, which comparison is the right one? To some extent this depends on the question: risk ratios may be more relevant as indicators of structural problems, but risk differences are what actually matter to individuals.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »
Homicide rates are harder to compare
I thought that infant mortality was also hard to compare, given different definitions of what counts as being born in relation to birth weights and gestational age (from memory, the US is still pretty bad, but not by as much as it first seems).
9 years ago
There are varying definitions of infant mortality, based on what counts as a fetal or neonatal death vs a stillbirth. I think, but I’m not certain, that the MoH figures are comparable to the US figures.
9 years ago
Age effects these statistics – Maori are a younger populations so they are going to have a higher rate of imprisonment so that difference is likely to be overestimated (but still bad).
EuroNZ women are likely to be older at their first birth which means they are at more risk so it’s likely that the baby mortality difference is underestimated.
(Or were these rates based on standardized populations because MoE do sometimes use standardised popualtion?)
9 years ago