Income and child mortality in developing countries: A systematic review and meta-analysis

Objective: We aimed to quantify the relationship betweennational income and infant and under-five mortality indeveloping countries.Design: We conducted a systematic literature search ofstudies that examined the relationship between incomeand child mortality (infant and/or under-five mortality)and meta-analysed their results.Setting: Developing countries.Main outcome measures: Child mortality (infant and /orunder-five mortality).Results: The systematic literature search identified 24 studies,which produced 38 estimates that examined the impactof income on the mortality rates. Using meta-analysis, weproduced pooled estimates of the relationship betweenincome and mortality. The pooled estimate of the relationshipbetween income and infant mortality before adjustingfor covariates is -0.95 (95% CI -1.34 to -0.57) and that forunder-five mortality is -0.45 (95% CI -0.79 to -0.11).After adjusting for covariates, pooled estimate of the relationshipbetween income and infant mortality is -0.33(-0.39 to -0.26) while the estimate for under-five mortalityis -0.28 (-0.37 to -0.19). If a country has an infant mortalityof 50 per 1000 live births and the gross domesticproduct per capita purchasing power parity increases by 10%, the infant mortality will decrease to 45 per 1000 livebirths.Conclusion: Income is an important determinant of childsurvival and this work provides a pooled estimate for therelationship. © The Royal Society of Medicine 2013.