title: Estimating the under-five mortality rate using a bayesian hierarchical time series model.
abstract: BACKGROUND
  Millennium Development Goal 4 calls for a reduction in the under-five mortality rate by two-thirds between 1990 and 2015, which corresponds to an annual rate of decline of 4.4%. The United Nations Inter-Agency Group for Child Mortality Estimation estimates under-five mortality in every country to measure progress. For the majority of countries, the estimates within a country are based on the assumption of a piece-wise constant rate of decline.
  
  
  RESULTS
  This paper proposes an alternative method to estimate under-five mortality, such that the underlying rate of change is allowed to vary smoothly over time using a time series model. Information about the average rate of decline and changes therein is exchanged between countries using a bayesian hierarchical model. Cross-validation exercises suggest that the proposed model provides credible bounds for the under-five mortality rate that are reasonably well calibrated during the observation period. The alternative estimates suggest smoother trends in under-five mortality and give new insights into changes in the rate of decline within countries.
  
  
  CONCLUSIONS
  The proposed model offers an alternative modeling approach for obtaining estimates of under-five mortality which removes the restriction of a piece-wise linear rate of decline and introduces hierarchy to exchange information between countries. The newly proposed estimates of the rate of decline in under-5 mortality and the uncertainty assessments would help to monitor progress towards Millennium Development Goal 4.
authors.affiliation: Department of Statistics and Applied Probability, National University of Singapore, Singapore, Singapore. alkema@nus.edu.sg
authors.forename: Leontine
authors.initials: L
authors.lastname: Alkema
authors.forename: Wei Ling
authors.initials: WL
authors.lastname: Ann
mesh_terms: D000465:Algorithms; D001499:Bayes Theorem; D002138:Calibration; D046688:Child Mortality / Q000639:trends*; D002675:Child, Preschool; D003906:Developing Countries / Q000706:statistics & numerical data; D014943:Global Health; D006801:Humans; D007223:Infant; D007226:Infant Mortality / Q000639:trends*; D007231:Infant, Newborn; D015233:Models, Statistical; D008962:Models, Theoretical; D012044:Regression Analysis; D013997:Time Factors; D014480:United Nations