Concentration indices of income related self-reported health: a meta-regression analysis

Proliferating evidence reporting on standardised cross-country concentration indexes of income related self-reported health is increasingly being used for policy evaluation. Nonetheless, limited efforts have been put forward to examine the extent to which such evidence is subject to any specific methodological and publication biases, given that studies rely upon survey data form different samples and both heterogeneous health system institutions and empirical strategies. We conduct the first study drawing upon appropriate statistical methods to examine the presence of publication bias in the health economics literature measuring health inequalities of self-reported health. We test for other biases including the effect of precision estimates based on meta-regression analysis (MRA). We account for a set of biases in estimates of income-related health inequalities that rely on concentration index-related methods and self-reported health measures. Our findings suggest evidence of publication bias that primarily depends on the cardinalisation of self-reported health and some evidence of study-specific precision.