نوع مقاله : مقاله پژوهشی

نویسندگان

• رضا نوبخت ¹
• احمد دراهکی ²
• علی قاسمی اردهایی ³

¹ استادیار جمعیت شناسی، دانشگاه پیام نور، تهران، ایران

² استادیار جمعیت شناسی، دانشگاه علامه طباطبائی، تهران، ایران

³ دانشیار جمعیت شناسی، دانشگاه پیام نور، تهران، ایران

چکیده

تعمیم میزان باروری کل موردنیاز برای سطح جانشینی برای تمامی کشورها و مناطق به‌ویژه زمانی که مناطق و کشورهای مورد مقایسه به لحاظ سطح توسعه‌یافتگی تفاوت‌های قابل‌توجهی داشته باشند صحیح نیست. مطالعه حاضر با استفاده از روش پرستون و همکاران 2003 و با استفاده از داده‌های ثبتی و سرشماری کشور طی سال‌های 1385 تا 1394 به برآورد میزان باروری کل موردنیاز برای سطح جانشینی در ایران و استان‌های مختلف آن پرداخته است. نتایج بیان‌کننده آن است میزان باروری کل موردنیاز برای سطح جانشینی برای سال 1390 و 1394، 1/2 فرزند است. همچنین نتایج بیانگر آن است میزان باروری کل موردنیاز برای سطح جایگزینی در استان‌های مختلف ایران یکسان نیست؛ و این شاخص برای سال 1390 برای استان‌ سیستان و بلوچستان 3/2، برای استان‌های خراسان جنوبی، چهارمحال و بختیاری، هرمزگان، کهکیلویه و بویراحمد، آذربایجان شرقی، ایلام، کرمانشاه و کردستان حدود 2/2 و برای سایر استان‌ها حدود 1/2 فرزند برای هر زن محاسبه گردید. توجه به این تفاوت‌ها و اهمیت نسبت جنسی در بدو تولد و همچنین احتمال بقای موالید دختر از تولد تا میانگین سن فرزندآوری ازجمله مباحثی است که در رسیدن به باروری سطح جانشینی در کشور باید موردتوجه قرار گیرد.

کلیدواژه‌ها

• باروری سطح جانشینی
• میزان باروری ویژه سنی
• احتمال بقاء موالید دختر
• میانگین سن مادری
• باروری استان‌های ایران

موضوعات

• جمعیت شناسی

عنوان مقاله [English]

Estimating the Total Fertility Rate Required for the Replacement Level in Iran Using Preston's Method from 2006 to 2015

نویسندگان [English]

• Reza Nobakht ¹
• Ahmad Dorahaki ²
• Ali Ghasemi Ardahaee ³

¹ Assistant professor in Demography, Payam Noor University, Tehran, Iran.

² Assistant professor in Demography, Allameh Tabataba'i University, Tehran, Iran.

³ Associate professor in Demography, Payam Noor University, Tehran, Iran.

چکیده [English]

 
It is not correct to generalize the total fertility rate required for the level of replacement for all countries and regions, especially when the compared regions and countries show considerable differences in terms of the level of development. Using the method of Preston et al. 2003 and utilizing the country's registration and census data from 1385 to 1394, the present study estimated the total fertility rate required for replacement level in Iran and its various provinces. The findings indicate that the total fertility rate required for replacement level is 1.2 children for the years 1390 and 1394. The results also show that the total fertility rate required for replacement level is not the same in different provinces of Iran. For 1390, this index for Sistan and Baluchistan province was 2.3, for the provinces of South Khorasan, Chahar Mahal and Bakhtiari, Hormozgan, Kahkiloyeh and Boyer Ahmad, East Azerbaijan, Ilam, Kermanshah, and Kurdistan it was 2.2 and for the other provinces, 2.1 children were calculated for each woman. Paying attention to these differences and the importance of sex ratio at birth and the probability of survival of female children from birth to average childbearing age are among the issues that should be considered in achieving the replacement level of fertility in the country.
Keywords: Replacement Level Fertility, Age-Specific Fertility Rate, Survival Probability of Female Children, Average Maternal Age, Fertility of Iranian Provinces.
Introduction
Several studies have been conducted in Iran in recent years in the field of methods of estimation and evaluation of fertility indicators. However, the methods used do not state that if the fertility of a region or province is at a certain level, according to the factors of survival probability, the number of women in each age group, the average maternal age, and the fertility of the replacement level in that province or region. How much will it be and will it be the same at 1/2 the replacement level at the same rate? What determines the level of difference between different regions in relation to replacement level fertility is the health status and in general, the level of development of the regions, which affects the rates and patterns of mortality, the probability of survival, and the average maternal age. Therefore, considering the difference in the level of development of regions and provinces of the country, this issue is raised as to whether this difference determines the fertility of different succession levels for different provinces. In this study, it will be pointed out which of the provinces' fertility has a greater distance from the normal fertility rate of the replacement level. One of the important points that the results of this study can provide, especially in the field of policymaking, is that despite the difference in the rate of succession in different provinces, the type of policymaking and its intensity and amount will also be different in different regions, and for each region and province will be planned based on the fertility of the replacement level and the distance from which the total fertility is calculated by a different method.
Literature Review
In their studies, some researchers have investigated the changes in the country's population at different times between censuses and estimated fertility rates (Aghajanian, 1991, 1995; Aghajanian & Mehryar, 1999, Mirzaee, 2005, Amani, 1997, 1999). Mirzaei, Sorahi and Naseri (1375) also compared the fertility indices for the years 1365 and 1370 using the indirect method and evaluated the results. Abbasi Shawazi et al. (2013) and Hosseini Chavoshi et al. (2013) also conducted various studies using the method of their children, the level, trend and pattern of fertility at the provincial and national levels, and using the consecutive censuses of 1365; 1375, 1385 and 1390 have been measured and analyzed. In these studies, the level and trend of fertility in Iran in recent decades from 1375 to 1390 have been investigated and the similarities and differences of the fertility pattern in the provinces have been depicted. The main point that remains in the empirical vacuum in all these studies is the issue of fertility below the replacement level for the country and the separation of different provinces. What was important in these studies was how much the changes in total fertility are and how the total fertility has changed in Iran, and this trend has occurred in most regions and provinces of the country.
Materials and Methods
In this research, the approach of Preston et al. (2003: 115) has been used to estimate replacement level fertility. The net reproduction rate is one of the basic concepts in the discussion of replacement-level fertility. By definition, this rate is the average number of live female births from a woman until the age of 50 if she is exposed to age-specific fertility rates and age-specific mortality rates in a given year. Preston et al. (2003) provide the following formula regarding the relationship between the net reproduction rate and the total fertility rate.
 
 )1(
 
In this study, the female population of age groups from the population and housing census of 1385, 1390, and 1395 and the birth and death statistics from the registration data were used.
Conclusion
The provincial results obtained from this study indicate that in provinces with high fertility, the total fertility required for the replacement level is also high. For example, in Sistan and Baluchistan province, where the total fertility rate in 2013 was 3.5 children, the total fertility rate required for the replacement level is 2.34 children. On the other hand, in Tehran province, where the total fertility rate is 1.40, the total fertility rate required for the replacement level is 1.2. Therefore, it seems that there is a significant and strong statistical correlation between the total fertility rate and the total fertility rate required for replacement. In adopting population policies, policymakers should pay attention to both the categories of development and replacement level fertility. It was observed that the fertility level of the succession of the provinces was different, so the type of policies and population planning should be different and variable based on each province.
 
 
 

کلیدواژه‌ها [English]

• Replacement Level Fertility
• Age-Specific Fertility Rate
• Survival Probability of Female Children
• Average Maternal Age
• Fertility of Iranian Provinces