Reducing socioeconomic health inequalities?: A questionnaire study of majorization and invariance conditions

We study the appeal of basic preference conditions that underpin health inequality indices, including the widely used concentration index. We did a lab experiment in which 349 respondents had to choose repeatedly between two policies that generated a distribution of income and health among five groups in society. We found stronger support for preference conditions that focus on inequality in the marginal distribution of health (and income) than for preference conditions that favor reduced correlation between both dimensions. Respondents’ choices were more in line with the principle of income related health transfers when policies did not affect the ranking of groups in terms of health. Respondents also expressed more concern about the correlation between income and health when health was expressed as a shortfall rather than an attainment. Support for the preference conditions was unaffected when all groups in society experienced the same absolute or relative health change.