A recent article by Benjamin Ho and Sita Nataraj Slavov, which I picked up via Marginal Revolution, argues that health inequality is falling. The argument is that life expectancy for the 1% dying at the bottom end of the age-at-death distribution has increased by more than the life expectancy for the 1% at the top. I’m struggling to think of much academic work being done to look at levels of health inequality in this way. However, I’m not sure what answering such questions could add.
Plenty of work has been done on how to measure health inequality. It seems a pretty heinous crime to talk about health equality without mentioning Culyer and Wagstaff. More recently, new models of health inequality have been developed that bare varying levels of equivalence to a standard concentration curve (see here, here, here, here etc). But the authors of the aforementioned article are really interested in pure health inequality, irrelevant of income or socio-economic indicators. Some work has been done here too (see here, here, here etc); indeed, the age-at-death distribution thing was done by Le Grand.
Pure health inequality
Health and income are very different in a number of ways, and it seems a misnomer to compare income inequality with health inequality. The most important difference, probably, is how society views the two. Society has some aversion to income inequality and also aversion to health inequality. However, we don’t just prefer a more equal distribution of health; we want equal full health (i.e. health maximisation). Assuming diminishing marginal returns to health care (in terms of health), we will tend to prioritise those in worse health and tend towards equality. I would argue that health can only increase indefinitely in terms of longevity. We may live longer and longer but I think ‘full health’ is a very real ceiling while we’re alive. It simply isn’t possible for a super-rich elite to develop in terms of health. What would these people be like? Bionic presumably, but that’s a different debate. Even if health could be amassed indefinitely it wouldn’t be, as health has no value in exchange.
For me (given society’s aversion to inequality, technological progress and a maximum level of health at any point in time), movement towards equal health seems inevitable. You don’t need to agree with the Grossman model to accept that health represents a kind of ‘stock’. It therefore bares more resemblance to wealth than to income. Health requires some effort to maintain, but not to the same degree as income. Ho and Slavov’s article also introduces the idea of a lottery; luck plays an important role here. Society reacts differently to an income shock (say, unemployment) than it does to a health shock (say, being hit by a car). As with income there might be fair and unfair inequalities, but either way society is going to attach more weight to reimbursing an individual’s loss of health than an individual’s loss of income (unless, maybe, the latter is a result of the former). The same applies to those dealt a nasty hand at birth. In countries where health care is dependent on ability to pay there will certainly be more of a link between health and income; and thus between health inequality and income inequality. In countries like the UK, income inequality seems less likely to affect health inequality.
Health is becoming more equal; I won’t disagree with that. But, for the reasons outlined above, this seems somewhat inevitable. I suppose that doesn’t mean we shouldn’t celebrate it, but it does raise into question the value of doing so when there are real discrepancies between different demographics’ health that need addressing.
Cynics may spot the benefit of such an approach for those at the top of the income distribution…
Thanks for sharing. Health inequalities that are preventable by reasonable measures are unfair. Putting them right is a matter of social justice.
Efforts to determine whether health inequalities have increased or decreased have generally suffered from a failure to recognize the ways that, for reasons inherent in the underlying risk distributions, standard measures of differences between the rates at which advantaged and disadvantaged groups experience an outcome tend to be systematically affected by the prevalence of an outcome. The most notable of these patterns is that whereby the rarer an outcome the greater tends to be the relative difference in experiencing it and the smaller tends to be the relative difference in avoiding it. Thus, as mortality and morbidity decline, relative differences in experiencing those outcomes tend to increase while relative differences in avoiding them tend to decrease; as rates of appropriate healthcare increase, relative differences in receipt of such care tend to decrease while relative differences in failing to receive such care tend to increase. Correspondingly, as morbidity and mortality decline, advantaged groups tend to experience larger proportionate declines in those outcomes than disadvantaged groups, while disadvantaged group send to experience larger proportionate increases in the opposite outcomes; as rates of appropriate healthcare increase, disadvantaged groups tend to experience larger proportionate increases in appropriate healthcare rates than advantaged groups, while advantaged groups tend to experience larger proportionate decreases in rates of failure to receive appropriate healthcare.
That is not to say that health or healthcare inequalities never change, but only that in order to determine directions of changes in such inequalities it is necessary to understand the ways measures tend to be affected by changes in the prevalence of an outcome. See my:
1. Can we actually measure health disparities? Chance 2006:19(2):47-51: http://www.jpscanlan.com/images/Can_We_Actually_Measure_Health_Disparities.pdf
2. Race and mortality. Society 2000;37(2):19-35 (reprinted in Current 2000 (Feb)):
3. The Misinterpretation of Health Inequalities in the United Kingdom, presented at the British Society for Populations Studies Conference 2006, Southampton, England, Sept. 18-20, 2006:
4. Measuring Health Inequalities by an Approach Unaffected by the Overall Prevalence of the Outcomes at Issue, presented at the Royal Statistical Society Conference 2009, Edinburgh, Scotland, Sept. 7-11, 2009: http://www.jpscanlan.com/images/Scanlan_RSS_2009_Presentation.ppt
5. The Mismeasure of Group Differences in the Law and the Social and Medical Sciences, Applied Statistics Workshop at the Institute for Quantitative Social Science at Harvard University, Cambridge, Massachusetts, Oct. 17, 2012: http://jpscanlan.com/images/Harvard_Applied_Statistic_Workshop.ppt
The concentration index behaves like the relative differences. As adverse outcomes decline, they tend to become more concentrated in disadvantaged groups. But the corresponding favorable outcome also tends to become more concentrated in the disadvantaged group. So as health improves, the concentration index will tend to show an increase in inequality as to the adverse outcome but a decrease in inequality as the favorable outcome. Table 1 of item 1 shows how lowering poverty in the US will tend to cause blacks to comprise a larger proportion of the poor, and a larger proportion of the non-poor, than they previously did. Table 1 of item 3 shows how lowering a test cutoff will tend to cause the lower-scoring group to comprise a higher proportion of those who fail, and a higher proportion of those who pass, than the group did at the higher cutoff. See also:
6. Concentration Index sub-page of Measuring Health Disparities page of jpscanlan.com:
7. Pages 171-72 of Carr-Hill R, Chalmers-Dixon P. The Public Health Observatory Handbook of Health Inequalities Measurement. Oxford: SEPHO; 2005: http://www.sepho.org.uk/extras/rch_handbook.aspx
The above discussion applies to dichotomies. Longevity is not a dichotomy. But it is a function of a dichotomy (mortality/survival). Thus, measures of differences in longevity also tend to be affected by general declines in morality. But the prevalence related patterns are difficult to predict, making it difficult to draw inferences based on departures from those patterns. See pages 6-7 and Table 2 of item 3.
[…] bottom and top, but this is only because there is a limit to the improvements healthcare can make (QALYs do not go higher than one). If there were no limit to health improvements our current system would not affect the […]
I agree that this study seems flawed, I imagine that the change in life expectancy at birth is almost entirely due to changes in infant mortality (which have been large), also this study doesn’t reflect quality of life. Also, what is happening in the rest of the distribution?! Given these results inequality could still have gone up by any normal measure!
But, I disagree that there is a tendency towards health equality for a couple of reasons:
I don’t think that it is possible to separate health and income at all since they are simultaneous, health is a necessary condition for income and income has effects on health above and beyond behaviour and consumption choices.
I think you a right to distinguish between (what Derek Parfit calls) egalitarianism and prioritarianism, since if just being more equal were the goal we could make the healthiest people sicker, whereas the priority view weights more heavily benefits to those worse off. But, our policies with regards to healthcare and public health don’t really reflect this view.
The big problem then is that the worst off health-wise are generally the poorest which many people think is not matter of luck but of choices – the NHS ironed out the inequalities due to luck then when you drink and get liver cancer it is your fault – a ignorant and simplistic view. To exacerbate the problem the healthiest (i.e. highest incomes) are also rent seekers and seek to reallocate resources in their favour. They don’t want to allocate more resources to the sick and poor.
As ever I’m making this up as I go along, so you could be right, but I don’t see how your points mean we wouldn’t tend towards health equality.
I agree that health and income shouldn’t be separated, but that’s what looking at pure health inequality requires. Nonetheless, I don’t see why income inequality should lead to health inequality because i) the rich have a lower capacity to get healthier than the poor and ii) the poor benefit from the positive externalities of the rich’s good health and health care. Therefore, so long as everybody is absolutely better off, health would tend towards equality.
In regard to choices, I think these are what would prevent us from actually reaching equal health. Though I would (as I’m sure you would too) question the extent to which drinking and getting liver cancer is a choice.
My main point though is that this is a fruitless debate. We know the causes of health inequality and we should be addressing these, not looking for reasons to celebrate.
Basically, i think that a reduction in health inequality requires an increase in redistribution that not really feasible due to peoples ideas of what is deserved.
How do you redistribute health? You can’t, really. Not in the same way as income. And why would you want to anyway? You could redistribute health care expenditure, sure, but that’s just one determinant of a person’s health outcomes.
Is health becoming more equal?! We’re all (well most) living longer, but the relative gaps are growing (and in some cases the absolute ones as well). In general we have public health improvment and widening relative inequality (some of which comes through clustering of poor health behaviours in more disadvantaged groups). It’s not at all inevitable that inequalities will narrow – they haven’t for decades – and many of the levers are outside the health service in the hands of government departments with objectives other than health whose budgets are being cut, rather than maintained (if you believe the government on this on the NHS). The levers in the NHS are not being used systematically and at scale (eg diabetes control, blood pressure etc) which would have a big and quick impact on life expectancy gaps (see the NAO on this, using DH’s own analysis). For a summary of all this see the signature Marmot graph – which need updating for sure and raises more questions than it answers – but shows the gradient on inequality in terms of life expectancy, and on disability-free life expectancy. So, lots to do, it won’t sort itself through the workings of economic theory (important and insightful though that is)!
You’re right, of course. I was only really thinking of inequality in the way the authors of said article characterise it – as the difference between the top and bottom 1%. I think conversion of these 2 specific groups is inevitable. But this approach distracts from deprivation-related inequalities that Marmot highlighted.
p.s. I haven’t actually read their Economics Bulletin study, but it looks pretty dodgy.