Long life is considered fortunate in every culture, so inequalities in mortality are fundamental to the way we think about whether a society is equitable. Many prominent recent studies argue that although most countries have seen dramatic declines in mortality through the decades, the gains have not been distributed equally. Indeed, several studies argue that when measured across educational groups and/or geographic areas, not only are mortality gaps widening, but also overall life expectancy is even falling, at least for some US groups. Given that the number of years that an individual can expect to live is such an important indicator of welfare, inequality in mortality is an important dimension in which overall societal inequality may be increasing.
Although inequalities in mortality are a subject of intrinsic interest that are often reﬂected in media headlines, they are not easy to measure in a consistent way over time or across countries. Currie and Schwandt (2016a) proposed an approach to examining inequalities in mortality that allowed all of the deaths for an entire population to be included (e.g. not only adults with income or education data). They build on a tradition of describing inequality by geographic areas. Their method remedies one of the problems in that literature, which is that differential migration can bias comparisons across areas. Also, it allows comparisons of changing distributions over time and across countries. The importance of health inequalities associated with places has recently been underlined by Chetty et al. (2016).
The approach is conceptually simple. First, rank areas from richest to poorest and then group them into 20 ‘bins’ of approximately equal size. The grouping of areas into bins helps to account for migration by ensuring that the analyst is always comparing population groups of ﬁxed size. Age-speciﬁc mortality rates can then be examined by age and gender group for each bin in any chosen year for which data are available (e.g. from a census). This procedure allows a consistent comparison of death rates in, for example, counties representing the poorest 5 per cent (or 10 or 20 per cent) of the population with those representing the richest ﬁve (or 10 or 20) per cent of the population across years.
The papers in this special issue use this approach to provide a comparison of the evolution of geographic inequalities in mortality in Canada, Czech Republic, Finland, France, Germany, the Netherlands, Norway, Portugal, Spain, the United Kingdom and the United States. As afﬂuent Western democracies, currently these countries all enjoy certain commonalities, and yet their experiences over the past 30 years have been quite diverse in terms of the evolution of both income and health inequalities. In part, this diversity represents the disparate impacts of larger historical forces, such as the fall of communism and global recessions, and in part it reﬂects different policy choices, such as the construction of the welfare state in Scandinavian countries and the continuing lack of universal health insurance in the US. It is precisely these different histories and differing policy institutions that make international comparisons a potentially fruitful avenue for understanding phenomena such as mortality rates or life expectancy, which depend on risk factors over the entire lifetime of the individuals concerned.