Income distribution and life expectancy: a critical appraisalBMJ 1995; 311 doi: http://dx.doi.org/10.1136/bmj.311.7015.1282 (Published 11 November 1995) Cite this as: BMJ 1995;311:1282
- Ken Judge, directora
- aKing's Fund Policy Institute, 11-13 Cavendish Square, London W1M 0AN
- Accepted 30 August 1995
In a series of papers published during the past decade Richard Wilkinson has advanced the view that income inequality is the key determinant of variations in average life expectancy at birth among developed countries. Yet a careful examination of the two sources of data on income distribution most often used by Wilkinson suggests that if they are analysed more appropriately they do not lend support to his claims. More recent data on income distribution is now available for several countries in the Organisation for Economic Development and Cooperation in the mid-1980s and for Great Britain from 1961 to 1991. The use of these data also casts doubt on the hypothesis that inequalities in the distribution of income are closely associated with variations in average life expectancy at birth among the richest nations of the world.
A paradox inherent in the scientific method is that, attached though we are to the hypotheses we formulate, we must really subject them to assault and search for circumstances that really test their resilience.1
Life expectancy is one of the key indicators of population health and economic development. Citizens of the poorest countries can expect to live for many decades less than those of the richest nations. Among the developed countries variations in the average expectation of life are not so great, but there are differences that cannot easily be explained by reference to economic prosperity. In 1988, for example, life expectancy at birth for men and women combined was almost five years greater in Japan than in Portugal.2 Several reasons have been advanced to account for these differences--from dietary influences such as the consumption of olive oil or fish to cultural factors such as national perceptions of self esteem--but many of them are peculiar to one country or a small group of …