Socio-economic inequalities in childhood mortality in low- and middle-income countries: a review of the international evidence.

INTRODUCTION: In low- and middle-income countries (LMICs), the probability of dying in childhood is strongly related to the socio-economic position of the parents or household in which the child is born. This article reviews the evidence on the magnitude of socio-economic inequalities in childhood mortality within LMICs, discusses possible causes and highlights entry points for intervention. Sources of data Evidence on socio-economic inequalities in childhood mortality in LMICs is mostly based on data from household surveys and demographic surveillance sites. AREAS OF AGREEMENT: Childhood mortality is systematically and considerably higher among lower socio-economic groups within countries. Also most proximate mortality determinants, including malnutrition, exposure to infections, maternal characteristics and health care use show worse levels among more deprived groups. The magnitude of inequality varies between countries and over time, suggesting its amenability to intervention. Reducing inequalities in childhood mortality would substantially contribute to improving population health and reaching the Millennium Development Goals (MDGs). AREAS OF CONTROVERSY: The contribution of specific determinants, including national policies, to childhood mortality inequalities remains uncertain. What works to reduce these inequalities, in particular whether policies should be universal or targeted to the poor, is much debated. AREAS TIMELY FOR DEVELOPING RESEARCH: The increasing political attention for addressing health inequalities needs to be accompanied by more evidence on the contribution of specific determinants, and on ways to ensure that interventions reach lower socio-economic groups.