The Sri Lanka Contraceptive Prevalence Survey was one of a series of surveys conducted in a number of countries under the sponsorship of the Westinghouse Health Systems of the U.S.A. The Sponsor's proposal to conduct the, survey came at a time when the country's family planning and population policy programs were reaching maturity and the need for measures of contraceptive prevalence to evaluate the programs was strong.
The Sri Lanka Contraceptive Prevalence Survey. (CPS) is a national sample survey designed to obtain information on contraceptive use and fertility. This survey was conducted in 1982 by the Department of Census and Statistics, Ministry of Plan Implementation, in collaboration with the Westinghouse Health Systems of Columbia, Maryland, U.S.A.
The Department of Census and Statisties through the CPS has obtained and tabulated data on levels of fertility, knowledge, use and availability of contraceptives for the entire island as well as for urban-rural areas. These data have been obtained by interviewing a nationally representative probability sample of about 4,500 ever-married women in the age group 15-49. The interviews were conducted by rigourously trained female interviewers of the Department of Census and Statistics under
The field work lasted a period of approximately two months from February to March 1982. Findings from the survey on a preliminary analysis were presented and discussed at a seminar held in Colombo on 4th August 1982.
Kind of Data
Sample survey data [ssd]
Unit of Analysis
all ever-married women 15-49 years old living in housing units one of which is defined as a place of residence separate from the other places of residence and with an independent access. (One or more households could occupy one housing units). The population living in places other than housing units such as institutions were excluded.
v1.0: Edited data, for internal use
Knowledge and use of contraceptive Practices
Impact of family planning programmes
Above themes were taken from the following objectives:
Short Term Objectives
(a) Collect for Sri Lanka, a body of data to ascertain the knowledge and the use of contraceptive practices and the current availability of contraceptives.
(b) Obtain information on the relationship between selected population characteristics and contraceptive knowledge and use.
Long Term Objectives
(a) Obtain for Sri Lanka, data on contraceptive behaviour for planning and evaluating the country's family planning programmes.
(b) Establish Contraceptive Prevalence Surveys as an evaluation tool for increasing the efficiency, effectiveness, and reliability of family planning programmes.
4. Northern Province
5. Eastern Province
6. North Western Province
7. North Central Province
8. Uva Province
9. Sabaragamuwa Province
All ever-married women 15-49 years old living in housing units.
Producers and sponsors
Department of Census and Statistics
Ministry of Finance and Planning
Westinghouse Health Systems, USA
Source of funds
The sample was a nationally representative probability sample drawn from a two stage design. In the first stage, a sample of Census Blocks was drawn from the predetermined strata. In the second stage a sample of housing units was drawn from each selected Census Block. All ever-married women aged 15-49 who lived in the selected housing units or who spent the
previous night in the unit were interviewed in detail.
First Stage Selection
The country was stratified into 2 strata as urban and rural areas. It was decided to select a sample of about 4,500 respondents spread out in 540 Census Blocks. A Census Block is an area assigned to an enumerator at the 1981 Census of Population and Housing for the purpose of enumeration. The Survey estimates were required at the national level and hence it was decided to allocate the sample proportional to the stratum population which was defind as the female population aged 15-49. This made it necessary to select 90 Census Blocks from the Urban Stratum and 450 from the rural stratum. The required number of blocks within each stratum was then selected from among the 24 administrative districts, the number selected from each district being proportional to the stratum population within the district.
Second Stage Selection
The Second' Stage consisted of selecting households from lists of housing units. These lists were obtained from the Pre-listing Forms prepared for the 1981 Census and were updated by the procedure outlined in the next section. The procedure for selection of households was as follows.
In the urban Census Blocks, a systematic sample of 15 housing units was selected from a list of such units. That is, starting from a randomly selected unit every unit at the end of an interval equal to one fifteenth the number of units in the block was selected in to the sample. In the rural Census Blocks, clusters of approximately ten housing units were formed and one cluster was selected at random from each block. All households in every housing unit whenever there was more than one in a unit were selected into the Sample.
Listing of Housing Units
The target population of the survey was all ever-married women 15-49 years old living in housing units. A housing unit was defined as a place of residence and with an independent access. One or more households could occupy one housing unit.
The population living in places other than housing units such as institutions were excluded. The effect of this exclusion the survey estimates was considered to be small as the population living in non-housing units at he 1981 census was a very small proportion of approximately 2 per cent. The sample frame for the survey was the prelisting Forms of the 1981 Census. A prelisting form was prepared for each Census Block and it contained a list of all housing units and non-housing units in the Census Block. The Pre-listing Forms of the selected Census Blocks were updated by the range Statistical Investigators of the Department. These officers were also the ones who prepared and later updated the lists initially for the Census and were quite familiar with the updating procedures. However, they were given specific instructions on updating by asking to delete the demolished and vacant units and to insert in the proper place any new units that had come up since the Census.
While the Survey was going on, it was found that some selected housing units were vacant, some were non-existent, and some could not be located by their addresses. However, the proportion of such units was quite small, only 2.7% and is unlikely to have caused a bias in the selection procedure.
Overall 94.9% of the selected housing units was interviewed. Of the 4666 eligible respondents in these households, 96% were successfully interviewed on the individual schedules. The lowest response rate recorded for any district is 92%.
The main reason for not completing the interviews in the small number of cases where they could not be completed was the absence of a competent respondent at home and the vacant or demolished state of the unit.
In the case of individual interviews the nonresponse was mainly due to the respondent being away from home and "other" miscellaneous reasons and the refusals were a neglegibly small proportion. Thus in this survey the overall response rates at both the household and individual interviews were quite high and there are no noteworthy differences in the response rates between
Dates of Data Collection
Data Collection Mode
Throughout the field work supervisors remained with their teams. The supervisors checked all completed schedules for internal consistency and to make sure that all instructions were adhered to. In addition, the co-ordinators spot checked
10 to 15 per cent of the interviews in each Census Block. Instructions were given to the team and the supervisors to make all stipulated checks on the completed questionnaires within a census block before moving to another block and to make
any call backs where necessary to keep the nonresponses to a minimum.
Data Collection Notes
Two pre-tests were carried out to test the questionnaire, one in November 1981 and the other in December 1981, in five areas not included in the Sample. The training for the pre-tests was carried out in close collaboration with the two Westinghouse advisers. The nine Statistical Officers who were enumerators at these pre-tests later functioned as Supervisors during field operations. These pre-tests were used to provide information about the length of the actual interviews, clarity of question wording, interpretation of questions by respondents, ease of data entry by interviewers and identification of categories to close the open-ended questions. After each pre-test, the questionnaire and other survey instruments- were modified to reflect the pretest experiences. The final questionnaire was then reviewed by a technical panel of experts and also by the National Steering Committee.
The training programme lasted a period of one week and included both class room work and field exercises. Class room work consisted of a lecture on reproductive physiology, familiarization with the questionnaire and other
survey documents, and a film on contraceptive use and role-playing interviews. The field exercises consisted of a series of practice interviews in the city suburbs under supervision and observation by the training staff. The training provided was very intensive, and detailed and covered techniques of interviewing and question by question instructions on the questionnaire. The interviewers were selected from the Department's Statistical investigators most of whom were University Graduates. As in earlier fertility surveys, female interviewers were selected because it was thought that they could easily establish the rapport that would enable respondents to discuss sexually related and sensitive topics.
Field work was carried out during the period February to March 1982. The Survey was given a fair degree of publicity through the media of the newspapers and the radio. For the purpose of organising the field work one coordinator was appointed to be in overall charge of all field work in each of the 9 provinces of the country.
A province consists of a number of districts ranging from 2 to 4. Interviews in each province was carried out by a team
of 5 interviewers headed by a supervisor. Thus, in all, there were 9 coordinators, 9 supervisors, and 45 interviewers in 9 teams. The coordinators were directly responsible for all technical, administrative, and financial aspects of field operations in their respective provinces. The major responsibilities of coordinators included the following:
1. Setting up temporary field offices;
2. Arranging for food, lodging and transportation for the field staff;
3. Correct identification of Sample Census Blocks and Sample Housing Units;
4. Ensuring the observance of correct procedures;
5. Delivery of all completed survey documents to Head Office.
The coordinators maintained regular contact with the Head Office and the District Statistical Office for instructions and feed backs. The supervisor of each team was responsible for overseeing the interviews and field coding, carrying out spot checks, and ensuring the correctness of procedures followed by interviewers and checking all completed survey documents.
Several measures were adopted to ensure the quality of data collected. During the first week of field work, all teams worked in and around Colombo City so that headquarters staff could observe and provide additional help and ensure
observance of correct procedures.
Department of Census and Statistics
Ministry of Finance and Planning
The survey questionnaire was an adaptation of the core questionnaire developed by the Westinghouse Health System to collect information relating to family planning management. The questionnaire has two main sections:
1. The Household schedule
2. Individual questionnaire
The household schedule was used for listing all females present regardless of their eligibility and for recording their background information. Names of females who usually resided in the household and of female visitors who spent the previous night in the household were recorded in this schedule. For each of these women, age, date of birth, and marital status were entered and based on these information the interviewers decided and recorded the eligibility of each woman for the individual interview. A woman was eligible for the individual interview if she met all of the following three criteria:
1. 15 through 49 years old.
2. Had been or was currently married.
3. Was in the household on the night prior to the interview.
The individual questionnaire consisted of the following five sections:-
Section I - Respondent's Background.
Section II - Fertility
Section III - Fertility Regulation
Section IV - Contraceptive Availability
Section V - Husband's Status
In adapting the core questionnaire to meet the country's requirements, some additional questions were included. Timing of future births and breast-feeding were added to Section II, motivation to adopt family planning, approval of family planning, and induced abortions were added to Section III, and problems related to family planning services was added to Section IV.
The questionnaire was translated into the two national1anguages, Sinhala and Tamil. The translations were independently re-translated into English and compared with the original to ensure exactness of the translation.
The questionnaires and all other survey documents were· printed by the Printing Division of the Department.
EDITING, CODING, TABULATION AND ANALYSIS
Seventeen of the interviewers and two supervisors were retained for manual editing and coding. These officers were given detailed instructions in editing and coding procedures by two senior officers who were also responsible for the preparation of edit specifications and the coding instructions. A coder was, on average, expected to edit, code and check 20 schedules per day. All responses to questions were given specific numeric, machine readable values. Since all but two questions used pre-coded responses, the work of the coders was fairly simple and it progressed smoothly. Computer processing of the data was carried out by the Data Processing Division of the Department of Census and Statistics.. Data were key punched directly from the schedules. Error printouts were returned to the editors and coders for correction. At the end of each correction, the files were updated and the edit program was re-run until a clean data file was obtained. The specified tabulations were prepared well within the allotted time of 2 ½ months from June to early August. Each tabulation was checked for likely errors and internal consistency and it was possible to make the necessary corrections without much delay. These tabulations were made available to any interested institution in order to enable the data from the survey to be used as early as possible.
A preliminary analysis of the data was carried out by a team of 6 staff' members of the Department of Census and Statistics. In this task they were assisted by the Westinghouse representative whose advice and comments were particularly valuable in the presentation of results. These findings were presented at a seminar held in August 1982 which was attended by about 30 professionals and administrators working in the field of population.
PRELIMINARY EVALUATION OF THE DATA
From the age distribution of females in household population of the survey with the 1981 Census age distribution of females, it is seen that the two distributions are remarkably similar; the largest difference between the percentages for any age group being only 0.4. It is noteworthy that in the survey a slightly higher percentage of children 0-4 years is reported than in the census where this group is likely to be under-enumerated. Thus, it appears that the quality of enumeration is similar at the CPS and the 1981 Census. Analysis of the 1981 Census age data (Retherford Etal, 1982) has shown that these data are of remarkably high quality in that the degree of age heaping and
misreporting is at a very low level. This comparison, it must be remembered, applies to the household population and no generalization can be made about the characteristics collected of individuals collected at the individual interviews.
Information Unit (Department of Census and Statistics)
Under the Census ordinance, micro data cannot be released with identifications for public use. Procedures are in place to ensure that information relating to any particular individual person, household or undertaking will be kept strictly confidential and will not be divulged to external parties. Information on individual or individual Household/establishment will not be divulged or published in such a form that will facilitate the identification of any particular person or establishment as the data have been collected under the Census ordinance, according to which the information at individual level cannot be divulged and such information is strictly
The dataset has been anonymized and is available as a Public Use Dataset. It is accessible to all for statistical and research purposes only, under the following terms and conditions:
1. The data and other materials will not be redistributed or sold to other individuals, institutions, or organizations without the written agreement.
2. The data will be used for statistical and scientific research purposes only. They will be used solely for reporting of aggregated information, and not for investigation of specific individuals or organizations.
3. No attempt will be made to re-identify respondents, and no use will be made of the identity of any person or establishment discovered inadvertently.
4. No attempt will be made to produce links among datasets provided by the Department or among data from the Department and other datasets that could identify individuals or organizations.
5. Any books, articles, conference papers, theses, dissertations, reports, or other publications that employ data obtained from the Department will cite the source of data in accordance with the Citation Requirement provided with each dataset.
6. An electronic copy of all reports and publications based on the requested data will be sent to the Department
The following rules apply to micro data released by the the Department of Census and Statistics.
* Only the request of Government Institutions, Recognized Universities, Students, and selected international agencies are entertained. However, the Data useres are required to strictly adhere to the term stipulated in the agreement form.
* All the data request should be made to Director General (DG) of the DCS as teh sole authority of releasing data is vested with the DG of the DCS. The DCS of Sri Lanka reserves sole right to approve or reject any data request made depending on the confidential nature of the data set and intended purpose of the study or analysis.
* Request for micro data should be made through the agreement form designed by DCS for this purpose (From D.R.1). The agreement form should be filled in triplicate and the Study/project proposal should accompany the filled agreement form. If requests are made fro the micro data of more than one survey, a separete agreement should be signed.
* If the data request is from a student a letter frome the respective Dept. Head/Dean/Supervisor, recommending the issue of data, should also be accompanied.
* If the request is approved only 25% of the data file is released at the first stage. The release of the total data file is considered only after reviewing the draft report prepared on the basis of the 25% sample data file.
* The released Data file should be used only for the specific study/Analysis mentioned in the agreement form and shall not be used for any other purpose without the prior approval of the Director general of the DCS. Moreover, Copies of the micro-data file, obtained from the DCS, shall not be giving to anyone else without the prior written approval of the Director General of the DCS.
* The draft report of the Study/Analysis should be submitted to the DCS and the concurrence of the DG of the DCS, should be obtained before publishing it. Once published, a copy of the final report should be submitted to the DCS.
Note - [Department = The Department of Census and Statistics (DCS)]
Source : http://www.statistics.gov.lk/databases/data%20dissemination/DataDissaPolicy_2007Oct26n.pdf
Department of Census and Statistics, Contraceptive Prevalence Survey 1982 [CPS1982], Version 1.0 of the public use dataset (July,2009), provided by the National Data Archive, Data Processing Division, www.statistics.gov.lk
Director General (Department of Census and Statistics)