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Regional and socioeconomic inequalities in infant mortality in Nigeria

  • Modupe Alake AyoadeEmail author


This study measures socioeconomic inequalities in infant mortality at the national and regional level in Nigeria based on secondary data from the 2003, 2008 and 2013 Nigeria demographic and health survey. Inequalities were assessed among groups defined by wealth, mother’s level of education and mother’s age using both simple range measures (Rate ratio and Rate difference) and more complex measures (Slope Index of Inequality, Concentration Index and Population Attributable Fraction). All measures identified significant inequalities in infant mortality amongst socioeconomic groups over space and time in Nigeria. Results showed that inequalities mostly favoured better-off groups. However, both relative and absolute inequalities between groups increased in some areas but generally narrowed to some degree or remained the same over time in most areas. Findings clearly show that a significant proportion of infant deaths could have been avoided in Nigeria over the 15 year period examined if socioeconomic inequalities in infant mortality rates had been eliminated/reduced by appropriate policy measures.


Infant mortality rates Socioeconomic inequalities Relative inequalities Absolute inequalities Nigeria 



The Author is grateful to ICF Macro, Calverton, USA for providing access to the 2003, 2008 and 2013 demographic and health survey data for Nigeria.

Compliance with ethical standards

Conflict of interest

There are no conflicts of interest. No funding was received for this research.

Ethical approval

Ethical approval was granted for the secondary analysis of existing demographic and health survey data after the removal of all identifying information of the respondents by the Institutional Review Board (IRB) of the ICF Macro at Calverton, USA in conjunction with the National Health Research Ethics Committee (NHREC) of the Federal Ministry of Health, Abuja, Nigeria.


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of GeographyUniversity of IbadanIbadanNigeria
  2. 2.IbadanNigeria

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