Patterns Levels and Trends in Fertility in Bangladesh 1982
The birth and death registration system is inadequate in Bangladesh to get reliable estimates of fertility and mortality. As a result the fertility and mortality estimates are derived from population census data or specially designed sample surveys. In the past, number of studies were undertaken to meet the data requirements for the development planning and policy makng particularly for the family planning administration and evaluation purposes.
The demographic survey conducted during 1960s and 1970s were as follows
- Demographic Survey in East Pahistan (DSEP), 1961-62
- Population Growth Estimation (PGE), 1962-65
- National impact Survey (NIS), 1968-69
- Bangladesh Retrospective Survey on Fertility and Mortality (BRSFM), 1974
- Bangladesh Fertility Survey (BFS), 1975-76
- Bangladesh Contraceptive Prevalence Survey (BCPS), 1979-80 and 1981
A similar retrospective survey was conducted by the Bangladesh Bureau of Statistics (BBS) in 1980. The survey was known as 'Base Line Demographic Survey (BLDS). The main purpose of the BLDS was to bound the population required for continuous sample registration system. The BLDS also collected information required for estimating current and cumulative fertility, cross-classified by the socio-economic variables. Since 1981, BBS have been continuing with the operation of sample vital registration system in the country. The 1981 Population Census was conducted using a simple questionnaire appropriate for optical mark reading (OMR). The census questionnaire was designed to collect information on nine personal characteristics only. Thereafter a sample survey was conducted during December1981 to February 1982 as a part of the main census and included questions suitable for indepth study of fertility and mortality and their interrelationships with socio-econornic variables.
The present report deals with levels, trends and differentials of fertility as obtained thi ough restrospective Survey of 1982. The report has been divided into seven chapters of which chapter on introduction discusses among others, background information and sample design followed by chapter two mentioning about the quality of age reporting of the survey data. The third chapter provides a short description regarding population characteristics. The fourth chapter describes the analysis on period fertility and its levels, trends and differentials followed by chapter fifth on cohort fertility and its levels, trends and differentials. The sixth chapter deals with the indirect estimates of fertility.
The last chapter summarises the results with concluding remarks.
Kind of Data
Sample survey data [ssd]
Producers and sponsors
Authoring entity/Primary investigators
BANGLADESH BUREAU OF STATISTICS
Statistics Division, Ministry of Planning
All the administrative units down to the village/enumeration area were geo-coded for the purpose of the population census 1981. An enumeration area (E.A) was an area consisting of approximately 100 households. Villages having more than 100 households were sub-divided into a number of E.A's. Maps were prepared for all the E.A's: prior to the census. It was decided to use the census E.A's as the first stage sampling frame for this survey.
The whole geographic area of Bangladesh constitutes the universe of enumeration. 79 paurashavas or municipalareas (including 4 Metropolitan cities - Chittagong, Dhaka, Khulna and Rajshahi) were considered as urban areas for the purpose of 1982 survey. All areas excluding these 79 paurashavas were treated as the rural universe. Urban area was divied into five strata. Each of the four Statistical Metropolitan Area (SMA) was treated as a seperate stratum. The urban areas (Municipalities) of the country other than these four SMA's constituted the fifth stratum. The rural area was divided into twenty strata, rural area of each old district being a strata.
Sampling Units (PSU and SSU)
As a complete list of census E.A's with full geo-code was available on the computer tape, it was used as the first stage sampling frame and Census Enumeration Area (E.A) was treated as the Primary Sampling Unit (PSU). In the second stage, a sub-sample of households was taken from each of the selected E.A.
Sampling Scheme and Selection of Samples
Linear systematic random sampling without replacement scheme was adopted at both stages. In the first stage, sample E.A's. (PSU's) were selected by the computer. For the rural area, the second stage sampling was done directly from the filled-in census schedules using random number tables. In the urban area, a household listing operation was done in the selected E.A 's and sample households were selected from the listed households by the trained statistical assistants at the head office using random number table;
Considering the population co-efficient of variations and availability of enumerator and time, 3500 Rural E.As and 1500 Urban E.As were included in the sample. 25 percent households from each selected E.A. were finally selected in the sample. In all 94769 household (urban 33347 and rural 61422) were enumerated which in turn covered 537474 population (urban 182292 and rural 355182).
Allocation of Samples
Initially, the sample E.As. were proportionately allocated to strata. However, minor adjustments were made for too small and too big strata. For required extent of reliability, each strata should have at least 125 sample E.As. Strata having less than 125 sample E.As. as per proportionate allocation, had been adjusted for 125 smaple E.As. by taking out some E.As. from big strata.