title: Ethnic differentials in under-five mortality in Nigeria.
abstract: OBJECTIVE
  There are huge regional disparities in under-five mortality in Nigeria. While a region within the country has as high as 222 under-five deaths per 1000 live births, the rate is as low as 89 per 1000 live births in another region. Nigeria is culturally diverse as there are more than 250 identifiable ethnic groups in the country; and various ethnic groups have different sociocultural values and practices which could influence child health outcome. Thus, the main objective of this study was to examine the ethnic differentials in under-five mortality in Nigeria.
  
  
  METHODS
  The study utilized 2008 Nigeria Demographic and Health Survey (NDHS) data. We analyzed data from a nationally representative sample drawn from 33,385 women aged 15-49 that had a total of 104,808 live births within 1993-2008. In order to examine ethnic differentials in under-five mortality over a sufficiently long period of time, our analysis considered live births within 15 years preceding the 2008 NDHS. The risks of death in children below age five were estimated using Cox proportional regression analysis. Results were presented as hazard ratios (HR) with 95% confidence intervals (CI).
  
  
  RESULTS
  The study found substantial differentials in under-five mortality by ethnic affiliations. For instance, risks of death were significantly lower for children of the Yoruba tribes (HR: 0.39, CI: 0.37-0.42, p < 0.001), children of Igbo tribes (HR: 0.58, CI: 0.55-0.61, p < 0.001) and children of the minority ethnic groups (HR: 0.66, CI: 0.64-0.68, p < 0.001), compared to children of the Hausa/Fulani/Kanuri tribes. Besides, practices such as plural marriage, having higher-order births and too close births showed statistical significance for increased risks of under-five mortality (p < 0.05).
  
  
  CONCLUSIONS
  The findings of this study stress the need to address the ethnic norms and practices that negatively impact on child health and survival among some ethnic groups in Nigeria.
authors.affiliation: a Programme in Demography and Population Studies , University of the Witwatersrand , Johannesburg , South Africa.
authors.forename: Sunday A
authors.initials: SA
authors.lastname: Adedini
authors.forename: Clifford
authors.initials: C
authors.lastname: Odimegwu
authors.forename: Eunice N S
authors.initials: EN
authors.lastname: Imasiku
authors.forename: Dorothy N
authors.initials: DN
authors.lastname: Ononokpono
mesh_terms: D000293:Adolescent; D000328:Adult; D001721:Birth Intervals / Q000208:ethnology; D001722:Birth Order; D046688:Child Mortality / Q000208:ethnology*; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007223:Infant; D007226:Infant Mortality / Q000208:ethnology*; D007231:Infant, Newborn; D050498:Live Birth / Q000208:ethnology; D008297:Male; D008393:Marriage / Q000208:ethnology; D008423:Maternal Age; D008875:Middle Aged; D009549:Nigeria / Q000453:epidemiology; D016016:Proportional Hazards Models; D055815:Young Adult
keywords: Nigeria; cultural practices; ethnicity; inequality; under-five mortality