Document Type : Original Article


Faculty Member, Department of Population and Health, National Institute for Population Research, Tehran, Iran


Background and aims: At least, during the last half-century, the mortality rate in Iran has decreased significantly, and life expectancy at birth has increased. To better understand the mechanisms of improving the health situation in Iran, this study sought to examine the contribution of age groups in improving life expectancy at birth during 1976 -2016.
Methods: The required life tables for the years 1976, 1986, and 1996 were taken from previous studies. Furthermore, life tables for 2006 and 2016 were calculated using the data from the registration system of the Ministry of Health. Then, the contribution of each age group in improving life expectancy in Iran by sex was estimated using the Arriaga decomposition method, and data analysis was conducted by creating a template in Excel software.
Results: The life expectancy at birth for men and women in Iran has increased by 18.7 and 21.5 years, respectively, during 1976–2016. Infant mortality was the most important factor in increasing life expectancy with 6.5 and 6 years for women and men, respectively. In addition, over time, the share of early deaths has decreased, and instead, old-age deaths have played a more prominent role in improving the life expectancy of men and women in Iran.
Conclusion: Today, increasing life expectancy for both sexes is mainly achieved through reducing the mortality of the older population, and achieving more years for life expectancy is mainly due to comprehensive development, especially reducing health inequalities and increasing life expectancy at older ages.


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