Changes in Socio-Economic Inequality in Neonatal Mortality in Iran Between 1995-2000 and 2005-2010: An Oaxaca Decomposition Analysis

Document Type : Original Article


1 Department of Health Management and Economics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

2 Health Management and Economics Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

3 Deputy of Public Health, Ministry of Health and Medical Education, Tehran, Iran

4 Department of Economics, Bu-Ali Sina University, Hamadan, Iran

5 Department of Public Health, Qom University of Medical Sciences, Qom, Iran

6 Centre for System Studies (CSS), Hull University Business School (HUBS), Hull York Medical School (HYMS), University of Hull, Hull, UK


Exploring changes in health inequality and its determinants over time is of policy interest. Accordingly, this study aimed to decompose inequality in neonatal mortality into its contributing factors and then explore changes from 1995-2000 to 2005-2010 in Iran.
Required data were drawn from two Iran’s demographic and health survey (DHS) conducted in 2000 and 2010. Normalized concentration index (CI) was used to measure the magnitude of inequality in neonatal mortality. The contribution of various determinants to inequality was estimated by decomposing concentration indices in 1995-2000 and 2005-2010. Finally, changes in inequality were investigated using Oaxaca-type decomposition technique.
Pro-rich inequality in neonatal mortality was declined by 16%, ie, the normalized CI dropped from -0.1490 in 1995-2000 to -0.1254 in 2005-2010. The largest contribution to inequality was attributable to mother’s education (32%) and household’s economic status (49%) in 1995-2000 and 2005-2010, respectively. Changes in mother’s educational level (121%), use of skilled birth attendants (79%), mother’s age at the delivery time (25-34 years old) (54%) and using modern contraceptive (29%) were mainly accountable for the decrease in inequality in neonatal mortality.
Policy actions on improving households’ economic status and maternal education, especially in rural areas, may have led to the reduction in neonatal mortality inequality in Iran.


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  • Receive Date: 14 March 2016
  • Revise Date: 14 September 2016
  • Accept Date: 17 September 2016
  • First Publish Date: 01 April 2017