Demographic and Health Survey 1993, Kenya
Kenya, 1993
Kenya. National Council for Population Development (NCPD), Kenya. Central Bureau of Statistics (CBS)
Identification
Survey ID Number
ken-ncpd-dhs-1993-v1
Title
Demographic and Health Survey 1993, Kenya
Subtitle
Kenya
Country
| Name | Country code |
|---|---|
| Kenya | KEN |
Study type
Demographic and Health Survey (standard) - DHS III
Series Information
The 1993 Kenya Demographic and Health Survey (KDHS) is the second survey of its kind to be carried out in the country; the first one was conducted in 1989.
Abstract
The 1993 Kenya Demographic and Health Survey (KDHS) was a nationally representative survey of 7,540 women age 15-49 and 2,336 men age 20-54. The KDHS was designed to provide information on levels and trends of fertility, infant and child mortality, family planning knowledge and use, maternal and child health, and knowledge of AIDS. In addition, the male survey obtained data on men's knowledge and attitudes towards family planning and awareness of AIDS. The data are intended for use by programme managers and policymakers to evaluate and improve family planning and matemal and child health programmes. Fieldwork for the KDHS took place from mid-February until mid-August 1993. All areas of Kenya were covered by the survey, except for seven northem districts which together contain less than four percent of the country's population.
The KDHS was conducted by the National Council for Population and Development (NCPD) and the Central Bureau of Statistics of the Government of Kenya. Macro International Inc. provided financial and technical assistance to the project through the intemational Demographic and Health Surveys (DHS) contract with the U.S. Agency for International Development.
OBJECTIVES
The KDHS is intended to serve as a source of population and health data for policymakers and the research community. It was designed as a follow-on to the 1989 KDHS, a national-level survey of similar size that was implemented by the same organisations. In general, the objectives of KDHS are to:
- assess the overall demographic situation in Kenya,
- assist in the evaluation of the population and health programmes in Kenya,
- advance survey methodology, and
- assist the NCPD to strengthen and improve its technical skills to conduct demographic and health surveys.
The KDHS was specifically designed to:
- provide data on the family planning and fertility behaviour of the Kenyan population to enable the NCPD to evaluate and enhance the National Family Planning Programme,
- measure changes in fertility and contraceptive prevalence and at the same time study the factors which affect these changes, such as marriage patterns, urban/rural residence, availability of contraception, breastfeeding habits and other socioeconomic factors, and
- examine the basic indicators of maternal and child health in Kenya.
KEY FINDINGS
The 1993 KDHS reinforces evidence of a major decline in fertility which was first revealed by the findings of the 1989 KDHS. Fertility continues to decline and family planning use has increased. However, the disparity between knowledge and use of family planning remains quite wide. There are indications that infant and under five child mortality rates are increasing, which in part might be attributed to the increase in AIDS prevalence.
The KDHS was conducted by the National Council for Population and Development (NCPD) and the Central Bureau of Statistics of the Government of Kenya. Macro International Inc. provided financial and technical assistance to the project through the intemational Demographic and Health Surveys (DHS) contract with the U.S. Agency for International Development.
OBJECTIVES
The KDHS is intended to serve as a source of population and health data for policymakers and the research community. It was designed as a follow-on to the 1989 KDHS, a national-level survey of similar size that was implemented by the same organisations. In general, the objectives of KDHS are to:
- assess the overall demographic situation in Kenya,
- assist in the evaluation of the population and health programmes in Kenya,
- advance survey methodology, and
- assist the NCPD to strengthen and improve its technical skills to conduct demographic and health surveys.
The KDHS was specifically designed to:
- provide data on the family planning and fertility behaviour of the Kenyan population to enable the NCPD to evaluate and enhance the National Family Planning Programme,
- measure changes in fertility and contraceptive prevalence and at the same time study the factors which affect these changes, such as marriage patterns, urban/rural residence, availability of contraception, breastfeeding habits and other socioeconomic factors, and
- examine the basic indicators of maternal and child health in Kenya.
KEY FINDINGS
The 1993 KDHS reinforces evidence of a major decline in fertility which was first revealed by the findings of the 1989 KDHS. Fertility continues to decline and family planning use has increased. However, the disparity between knowledge and use of family planning remains quite wide. There are indications that infant and under five child mortality rates are increasing, which in part might be attributed to the increase in AIDS prevalence.
Kind of Data
Sample survey data
Unit of Analysis
- Household
- Women age 15-49
- Men age 20-54
- Children under five
- Women age 15-49
- Men age 20-54
- Children under five
Scope
Notes
The 1993 Kenya Demographic and Health Survey covers the following topics:
- Anthropometry
- Antenatal and delivery care
- Breastfeeding and weaning practices
- Contraception
- Family planning
- Fertility régulation
- Husband's Survey
- Infant and child mortality
- Knowledge and use of family planning methods,
- Knowledge of AIDS
- Men's Survey
- Maternal and child health
- Nuptiality
- Polygyny
- Post partum insuceptibility
- Service Availability
- Vaccinations and health of children under age five
- Anthropometry
- Antenatal and delivery care
- Breastfeeding and weaning practices
- Contraception
- Family planning
- Fertility régulation
- Husband's Survey
- Infant and child mortality
- Knowledge and use of family planning methods,
- Knowledge of AIDS
- Men's Survey
- Maternal and child health
- Nuptiality
- Polygyny
- Post partum insuceptibility
- Service Availability
- Vaccinations and health of children under age five
Coverage
Geographic Coverage
The 1993 KDHS sample is national in scope, with the exclusion of all three districts in North Eastern Province and four other northern districts (Samburu and Turkana in Rift Valley Province and Isiolo and 4 Marsabit in Eastern Province). Together the excluded areas account for less than 4 percent of Kenya's population.
Universe
The population covered by the 1993 KDHS is defined as the universe of all women age 15-49 in Kenya and all husband age 20-54 living in the household.
Producers and sponsors
Primary investigators
| Name |
|---|
| Kenya. National Council for Population Development (NCPD) |
| Kenya. Central Bureau of Statistics (CBS) |
Producers
| Name | Role |
|---|---|
| Macro International Inc | Technical assistance |
Funding Agency/Sponsor
| Name | Abbreviation |
|---|---|
| U.S. Agency for International Development | USAID |
Sampling
Sampling Procedure
The sample for the 1993 KDHS was national in scope, with the exclusion of all three districts in Northeastern Province and four other northern districts (Isiolo and Marsabit from Eastern Province and Samburu and Turkana from Rift Valley Province). Together the excluded areas account for less than four percent of Kenya's population. The KDHS sample points were selected from a national master sample maintained by the Central Bureau of Statistics, the third National Sample Survey and Evaluation Programme (NASSEP-3), which is an improved version of NASSEP2 used in the 1989 survey. This master sample follows a two-stage design, stratified by urban-rural residence, and within the rural stratum, by individual district. In the first stage, 1989 census enumeration areas (EAs) were selected with probability proportional to size. The selected EAs were segmented into the expected number of standard-sized clusters to form NASSEP clusters. The entire master sample consists of 1,048 rural and 325 urban ~ sample points ("clusters"). A total of 536 clusters---92 urban and 444 rural--were selected for coverage in the KDHS. Of these, 520 were successfully covered. Sixteen clusters were inaccessible for various reasons.
As in the 1989 KDHS, selected districts were oversampled in the 1993 survey in order to produce more reliable estimates for certain variables at the district level. Fifteen districts were thus targetted in the 1993 KDHS: Bungoma, Kakamega, Kericho, Kilifi, Kisii, Machakos, Meru, Murang'a, Nakuru, Nandi, Nyeri, Siaya, South Nyanza, Taita-Taveta, and Uasin Gishu; in addition, Nairobi and Mombasa were also targetted. Although six of these districts were subdivided shortly before the sample design was finalised) the previous boundaries of these districts were used for the KDHS in order to maintain comparability with the 1989 survey. About 400 rural households were selected in each of these 15 districts, just over 1000 rural households in other districts, and about 18130 households in urban areas, for a total of almost 9,000 households. Due to this oversampling, the KDHS sample is not self-weighting at the national level.
After the selection of the KDHS sample points, fieldstaff from the Central Bureau of Statistics conducted a household listing operation in January and early February 1993, immediately prior to the launching of the fieldwork. A systematic sample of households was then selected from these lists, with an average "take" of 20 households in the urban clusters and 16 households in rural clusters, for a total of 8,864 households selected. Every other household was identified as selected for the male survey, meaning that, in addition to interviewing all women age 15-49, interviewers were to also interview all men age 20-54. It was expected that the sample would yield interviews with approximately 8,000 women age 15-49 and 2,500 men age 20-54.
As in the 1989 KDHS, selected districts were oversampled in the 1993 survey in order to produce more reliable estimates for certain variables at the district level. Fifteen districts were thus targetted in the 1993 KDHS: Bungoma, Kakamega, Kericho, Kilifi, Kisii, Machakos, Meru, Murang'a, Nakuru, Nandi, Nyeri, Siaya, South Nyanza, Taita-Taveta, and Uasin Gishu; in addition, Nairobi and Mombasa were also targetted. Although six of these districts were subdivided shortly before the sample design was finalised) the previous boundaries of these districts were used for the KDHS in order to maintain comparability with the 1989 survey. About 400 rural households were selected in each of these 15 districts, just over 1000 rural households in other districts, and about 18130 households in urban areas, for a total of almost 9,000 households. Due to this oversampling, the KDHS sample is not self-weighting at the national level.
After the selection of the KDHS sample points, fieldstaff from the Central Bureau of Statistics conducted a household listing operation in January and early February 1993, immediately prior to the launching of the fieldwork. A systematic sample of households was then selected from these lists, with an average "take" of 20 households in the urban clusters and 16 households in rural clusters, for a total of 8,864 households selected. Every other household was identified as selected for the male survey, meaning that, in addition to interviewing all women age 15-49, interviewers were to also interview all men age 20-54. It was expected that the sample would yield interviews with approximately 8,000 women age 15-49 and 2,500 men age 20-54.
Response Rate
A total of 8,805 households was selected for the survey, of which 7,950 were successfully interviewed. The shortfall is primarily due to dwellings being vacant or in which the inhabitants had left for an extended period at the time they were visited by the interviewing teams. Of the 8,185 households that were found, 97 percent were interviewed. Within these households, 7,952 women were identified as eligible for an individual interview and of these, 7,540, or 95 percent, were interviewed. In the one half of the households that were selected for inclusion in the male survey, 2,762 eligible men were identified, of which 2,336, or 85 percent, were interviewed. Response rates were higher in rural than in urban areas.
Data Collection
Dates of Data Collection
| Start | End |
|---|---|
| 1993-02 | 1993-08 |
Data Collection Mode
Face-to-face
Data Collection Notes
TRAINING
The KDHS questionnaires were pretested in October 1992. Sixteen interviewers (one woman and one man for each of the eight local languages) were trained for two weeks at the Masaku County Training Centre in Machakos town. Four of the 16 had participated in the 1989 KDHS and several others had other experience with fieldwork, Trainers included several officers from the NCPD, the CBS, Macro, and several guest lecturers from other agencies (e.g., the District Public Health Nurse, the District Statistical Officer). Since the main purpose of the pretest was to check the translations, trainees were asked to compare the English version with that in their own languages and to make back translations into English of key questions.
After training, the eight teams spent eight days in the field conducting interviews under the observation of six officers from NCPD headquarters. Altogether, 185 Woman's and 183 Man's Questionnaires were completed. In addition, several of the NCPD officers tried filling in a preliminary version of the Services Availability Questionnaire. The field teams then spent two days in Nairobi in debriefing meetings, describing the fieldwork and suggesting modifications to the questionnaires. On the basis of these suggestions, revisions in the wording and translations of the questionnaires were made.
In November 1992, NCPD officers visited several districts to recruit candidates for fieldstaff positions for the main survey. Recruitment criteria included ability to speak at least one of the eight local languages in which the survey was conducted, educational attainment, maturity, ability to spend one month in training and at least four months in the field and experience in other surveys. A total of 102 trainees were recruited.
Training for the main survey was conducted at the Mathari Pastoral Centre in Nyeri for four weeks (from 18 January to 12 February 1992). In order to facilitate training, participants were divided into two groups and almost all of the classroom training was done separately. A plenary hall was used for the opening and closing ceremonies and for short lectures when it was beneficial to have the whole group together. Two NCPD officers were assigned full-time to each group, with several other officers assisting periodically. Lectures on family planning were presented by two women from the Nyeri branch of the Family Planning Association of Kenya. Two staff from Macro assisted full-time, while one Macro consultant assisted a CBS officer in the anthropometric measurement training for one week.
Most of the first week of training consisted of lectures on how to fill the questionnaires, with mock interviews between participants after each section was explained. The second week was divided between completing the explanation of the questionnaire and training on how to take height and weight measurements. Generally, one group would spend half the day on anthropometric training and the otherhalfin the classroom. Anthropometric training consisted of explanations of how to use the equipment, followed by practice within the group of trainees, and then practice on children during visits to two nearby nursery schools and the Provincial Hospital. The third week was spent in mock interviews on the whole questionnaire, discussion of the local language versions of the questionnaires, and two days of field practice interviewing in the community. The fourth week was spent in another day of field practice, training supervisors and field editors in questionnaire editing and filling out the services availability questionnaire, administering a test, checking and dividing the questionnaires and other field equipment by team, and the closing ceremony. In addition, during the last three days, a separate training course was held for all the District Population Officers and several of the District Statistical Officers.
Trainees who performed satisfactorily in the training programme were selected as interviewers, while those whose performance was rated as superior were selected as supervisors and/or field editors. Those whose performance was satisfactory, but who either could not travel in the field or whose native language was one in which there was a surfeit of interviewers, were selected as data processing staff.
FIELDWORK
The fieldwork for the KDHS was carded out by 12 interviewing teams. Each consisted of one supervisor, one field editor, 4-7 female interviewers, one male interviewer and one driver;, however, due to its lighter workload, the Masai team consisted of one supervisor/editor, two female interviewers, one male interviewer and one driver. In total, there were 12 supervisors, 11 field editors, 60 female interviewers, 12 male interviewers and 12 drivers. In addition, each team was assigned a fieldwork coordinator, generally one of the trainers, who spent a considerable amount of time in the field starting the team off and periodically checking on them. In addition, the District Population Officers assisted in the logistical aspects of fieldwork. Fieldwork commenced on 18 February and was completed on 15 August 1993.
Data on the time the interview began and ended are available from the Woman's Questionnaires for most respondents. The data indicate that interviews with eligible women took an average of 42 minutes, excluding the time taken to fill the household questionnaire and to take anthropometric measurements. Slightly over one-quarter took less than 30 minutes to complete, while one-third took 30-44 minutes; 23 percent took 45-59 minutes and 15 percent took more than one hour.
The KDHS questionnaires were pretested in October 1992. Sixteen interviewers (one woman and one man for each of the eight local languages) were trained for two weeks at the Masaku County Training Centre in Machakos town. Four of the 16 had participated in the 1989 KDHS and several others had other experience with fieldwork, Trainers included several officers from the NCPD, the CBS, Macro, and several guest lecturers from other agencies (e.g., the District Public Health Nurse, the District Statistical Officer). Since the main purpose of the pretest was to check the translations, trainees were asked to compare the English version with that in their own languages and to make back translations into English of key questions.
After training, the eight teams spent eight days in the field conducting interviews under the observation of six officers from NCPD headquarters. Altogether, 185 Woman's and 183 Man's Questionnaires were completed. In addition, several of the NCPD officers tried filling in a preliminary version of the Services Availability Questionnaire. The field teams then spent two days in Nairobi in debriefing meetings, describing the fieldwork and suggesting modifications to the questionnaires. On the basis of these suggestions, revisions in the wording and translations of the questionnaires were made.
In November 1992, NCPD officers visited several districts to recruit candidates for fieldstaff positions for the main survey. Recruitment criteria included ability to speak at least one of the eight local languages in which the survey was conducted, educational attainment, maturity, ability to spend one month in training and at least four months in the field and experience in other surveys. A total of 102 trainees were recruited.
Training for the main survey was conducted at the Mathari Pastoral Centre in Nyeri for four weeks (from 18 January to 12 February 1992). In order to facilitate training, participants were divided into two groups and almost all of the classroom training was done separately. A plenary hall was used for the opening and closing ceremonies and for short lectures when it was beneficial to have the whole group together. Two NCPD officers were assigned full-time to each group, with several other officers assisting periodically. Lectures on family planning were presented by two women from the Nyeri branch of the Family Planning Association of Kenya. Two staff from Macro assisted full-time, while one Macro consultant assisted a CBS officer in the anthropometric measurement training for one week.
Most of the first week of training consisted of lectures on how to fill the questionnaires, with mock interviews between participants after each section was explained. The second week was divided between completing the explanation of the questionnaire and training on how to take height and weight measurements. Generally, one group would spend half the day on anthropometric training and the otherhalfin the classroom. Anthropometric training consisted of explanations of how to use the equipment, followed by practice within the group of trainees, and then practice on children during visits to two nearby nursery schools and the Provincial Hospital. The third week was spent in mock interviews on the whole questionnaire, discussion of the local language versions of the questionnaires, and two days of field practice interviewing in the community. The fourth week was spent in another day of field practice, training supervisors and field editors in questionnaire editing and filling out the services availability questionnaire, administering a test, checking and dividing the questionnaires and other field equipment by team, and the closing ceremony. In addition, during the last three days, a separate training course was held for all the District Population Officers and several of the District Statistical Officers.
Trainees who performed satisfactorily in the training programme were selected as interviewers, while those whose performance was rated as superior were selected as supervisors and/or field editors. Those whose performance was satisfactory, but who either could not travel in the field or whose native language was one in which there was a surfeit of interviewers, were selected as data processing staff.
FIELDWORK
The fieldwork for the KDHS was carded out by 12 interviewing teams. Each consisted of one supervisor, one field editor, 4-7 female interviewers, one male interviewer and one driver;, however, due to its lighter workload, the Masai team consisted of one supervisor/editor, two female interviewers, one male interviewer and one driver. In total, there were 12 supervisors, 11 field editors, 60 female interviewers, 12 male interviewers and 12 drivers. In addition, each team was assigned a fieldwork coordinator, generally one of the trainers, who spent a considerable amount of time in the field starting the team off and periodically checking on them. In addition, the District Population Officers assisted in the logistical aspects of fieldwork. Fieldwork commenced on 18 February and was completed on 15 August 1993.
Data on the time the interview began and ended are available from the Woman's Questionnaires for most respondents. The data indicate that interviews with eligible women took an average of 42 minutes, excluding the time taken to fill the household questionnaire and to take anthropometric measurements. Slightly over one-quarter took less than 30 minutes to complete, while one-third took 30-44 minutes; 23 percent took 45-59 minutes and 15 percent took more than one hour.
Questionnaires
Questionnaires
The questionnaire for each DHS can be found as an appendix in the final report for each study.
Four types of questionnaires were used for the KDHS: a Household Questionnaire, a Woman's Questionnaire, a Man's Questionnaire and a Services Availability Questionnaire. The contents of these questionnaires were based on the DHS Model B Questionnaire, which is designed for use in countries with low levels of contraceptive use. Additions and modifications to the model questionnaires were made during a series of meetings organised around specific topics or sections of the questionnaires (e.g., fertility, family planning). The NCPD invited staff from a variety of organisations to attend these meetings, including the Population Studies Research Institute and other departments of the University of Nairobi, the Woman's Bureau, and various units of the Ministry of Health. The questionnaires were developed in English and then translated into and printed in Kiswahili and eight of the most widely spoken local languages in Kenya (Kalenjin, Kamba, Kikuyu, Kisii, Luhya, Luo, Meru, and Mijikenda).
a) The Household Questionnaire was used to list all the usual members and visitors of selected households. Some basic information was collected on the characteristics of each person listed, including his/her age, sex, education, and relationship to the head of the household. The main purpose of the Household Questionnaire was to identify women and men who were eligible for individual interview. In addition, information was collected about the dwelling itself, such as the source of water, type of toilet facilities, materials used to construct the house, and ownership of various consumer goods.
b) The Woman's Questionnaire was used to collect information from women aged 15-49. These women were asked questions on the following topics: Background characteristics (age, education, religion, etc.), Reproductive history, Knowledge and use of family planning methods, Antenatal and delivery care, Breastfeeding and weaning practices, Vaccinations and health of children under age five, Marriage, Fertility preferences, Husband's background and respondent's work, Awareness of AIDS. In addition, interviewing teams measured the height and weight of children under age five (identified through the birth histories) and their mothers.
c) Information from a subsample of men aged 20-54 was collected using a Man's Questionnaire. Men were asked about their background characteristics, knowledge and use of family planning methods, marriage, fertility preferences, and awareness of AIDS.
d) The Services Availability Questionnaire was used to collect information on the health and family planning services obtained within the cluster areas. One service availability questionnaire was to be completed in each cluster.
Four types of questionnaires were used for the KDHS: a Household Questionnaire, a Woman's Questionnaire, a Man's Questionnaire and a Services Availability Questionnaire. The contents of these questionnaires were based on the DHS Model B Questionnaire, which is designed for use in countries with low levels of contraceptive use. Additions and modifications to the model questionnaires were made during a series of meetings organised around specific topics or sections of the questionnaires (e.g., fertility, family planning). The NCPD invited staff from a variety of organisations to attend these meetings, including the Population Studies Research Institute and other departments of the University of Nairobi, the Woman's Bureau, and various units of the Ministry of Health. The questionnaires were developed in English and then translated into and printed in Kiswahili and eight of the most widely spoken local languages in Kenya (Kalenjin, Kamba, Kikuyu, Kisii, Luhya, Luo, Meru, and Mijikenda).
a) The Household Questionnaire was used to list all the usual members and visitors of selected households. Some basic information was collected on the characteristics of each person listed, including his/her age, sex, education, and relationship to the head of the household. The main purpose of the Household Questionnaire was to identify women and men who were eligible for individual interview. In addition, information was collected about the dwelling itself, such as the source of water, type of toilet facilities, materials used to construct the house, and ownership of various consumer goods.
b) The Woman's Questionnaire was used to collect information from women aged 15-49. These women were asked questions on the following topics: Background characteristics (age, education, religion, etc.), Reproductive history, Knowledge and use of family planning methods, Antenatal and delivery care, Breastfeeding and weaning practices, Vaccinations and health of children under age five, Marriage, Fertility preferences, Husband's background and respondent's work, Awareness of AIDS. In addition, interviewing teams measured the height and weight of children under age five (identified through the birth histories) and their mothers.
c) Information from a subsample of men aged 20-54 was collected using a Man's Questionnaire. Men were asked about their background characteristics, knowledge and use of family planning methods, marriage, fertility preferences, and awareness of AIDS.
d) The Services Availability Questionnaire was used to collect information on the health and family planning services obtained within the cluster areas. One service availability questionnaire was to be completed in each cluster.
Data Processing
Data Editing
All questionnaires for the KDHS were returned to the NCPD headquarters for data processing. The processing operation consisted of office editing, coding of open-ended questions, data entry, and editing errors found by the computer programs. One NCPD officer, one data processing supervisor, one questionnaire administrator, two office editors, and initially four data entry operators were responsible for the data processing operation. Due to attrition and the need to speed up data processing, another four data entry operators were later hired temporarily. The data were processed on seven microcomputers, two of which were supplied specifically for the survey. The DHS data entry and editing programs were written in ISSA (Integrated System for Survey Analysis). Data processing commenced in early March and was completed by mid-September 1993.
Data Appraisal
Estimates of Sampling Error
Sampling errors, on the other hand, can be evaluated statistically. The sample of respondents selected in the KDHS is only one of many samples that could have been selected from the same population, using the same design and expected size. Each of these samples would yield results that differ somewhat from the results of the actual sample selected. The sampling error is a measure of the variability between all possible samples. Although the degree of variability is not known exactly, it can be estimated from the survey results.
Sampling error is usually measured in terms of the standard error for a particular statistic (mean, percentage, etc.), which is the square root of the variance. The standard error can be used to calculate confidence intervals within which the true value for the population can reasonably be assumed to fall. For example, for any given statistic calculated from a sample survey, the value of that statistic will fall within a range of plus or minus two times the standard error of that statistic in 95 percent of all possible samples of identical size and design.
If the sample of respondents had been selected as a simple random sample, it would have been possible to use straightforward formulas for calculating sampling errors. However, the KDHS sample is the result of a two-stage stratified design, and, consequently, it was necessary to use more complex formulas. The computer software used to calculate sampling errors for the KDHS is the ISSA Sampling Error Module (ISSAS). This module used the Taylor linearization method of variance estimation for survey estimates that are means or proportions. The Jacknife repeated replication method is used for variance estimation of more complex statistics such as fertility and mortality rates.
In addition to the standard errors, ISSAS computes the design effect (DEFT) for each estimate, which is defined as the ratio between the standard error using the given sample design and the standard error that would result if a simple random sample had been used. A DEFT value of 1.0 indicates that the sample design is as efficient as a simple random sample, while a value greater than 1.0 indicates the increase in the sampling error due to the use of a more complex and less statistically efficient design. ISSAS also computes the relative error and confidence limits for the estimates.
Sampling errors for the KDHS are calculated for selected variables considered to be of primary interest. The results are presented in an appendix to the Final Report for the country as a whole, for urban and rural areas, and for the nine provinces. In addition, sampling errors for contraceptive variables are calculated for certain smaller subsamples of female respondents, namely, Mombasa and the rural areas of the special districts. For each variable, the type of statistic (mean, proportion, or rate) and the base population are given in Table B. 1 in the Final Report's appendix. Tables B.2 to B. 17 present the value of the statistic (R), its standard error (SE), the number of unweighted (N) and weighted (WN) cases, the design effect (DEFT), the relative standard error (SE/R), and the 95 percent confidence limits (R+2SE), for each variable. In general, the relative standard error for most estimates for the country as a whole is small, except for estimates of very small proportions. There are some differentials in the relative standard error for the estimates of sub-populations such as geographical areas. For example, for the variable Children ever born to women aged 15-49, the relative standard error as a percent of the estimated mean for the whole country, for urban areas and for Nairobi is 1.3 percent, 4.3 percent, and 7.9 percent, respectively.
The confidence interval (e.g., as calculated for Children ever born to women aged 15-49) can be interpreted as follows: the overall average from the national sample is 3.167 and its standard error is .042. Therefore, to obtain the 95 percent confidence limits, one adds and subtracts twice the standard error to the sample estimate, ie. 3.167+.084. There is a high probability (95 percent) that the true average number of children ever born to all women aged 15 to 49 is between 3.083 and 3.251.
Sampling error is usually measured in terms of the standard error for a particular statistic (mean, percentage, etc.), which is the square root of the variance. The standard error can be used to calculate confidence intervals within which the true value for the population can reasonably be assumed to fall. For example, for any given statistic calculated from a sample survey, the value of that statistic will fall within a range of plus or minus two times the standard error of that statistic in 95 percent of all possible samples of identical size and design.
If the sample of respondents had been selected as a simple random sample, it would have been possible to use straightforward formulas for calculating sampling errors. However, the KDHS sample is the result of a two-stage stratified design, and, consequently, it was necessary to use more complex formulas. The computer software used to calculate sampling errors for the KDHS is the ISSA Sampling Error Module (ISSAS). This module used the Taylor linearization method of variance estimation for survey estimates that are means or proportions. The Jacknife repeated replication method is used for variance estimation of more complex statistics such as fertility and mortality rates.
In addition to the standard errors, ISSAS computes the design effect (DEFT) for each estimate, which is defined as the ratio between the standard error using the given sample design and the standard error that would result if a simple random sample had been used. A DEFT value of 1.0 indicates that the sample design is as efficient as a simple random sample, while a value greater than 1.0 indicates the increase in the sampling error due to the use of a more complex and less statistically efficient design. ISSAS also computes the relative error and confidence limits for the estimates.
Sampling errors for the KDHS are calculated for selected variables considered to be of primary interest. The results are presented in an appendix to the Final Report for the country as a whole, for urban and rural areas, and for the nine provinces. In addition, sampling errors for contraceptive variables are calculated for certain smaller subsamples of female respondents, namely, Mombasa and the rural areas of the special districts. For each variable, the type of statistic (mean, proportion, or rate) and the base population are given in Table B. 1 in the Final Report's appendix. Tables B.2 to B. 17 present the value of the statistic (R), its standard error (SE), the number of unweighted (N) and weighted (WN) cases, the design effect (DEFT), the relative standard error (SE/R), and the 95 percent confidence limits (R+2SE), for each variable. In general, the relative standard error for most estimates for the country as a whole is small, except for estimates of very small proportions. There are some differentials in the relative standard error for the estimates of sub-populations such as geographical areas. For example, for the variable Children ever born to women aged 15-49, the relative standard error as a percent of the estimated mean for the whole country, for urban areas and for Nairobi is 1.3 percent, 4.3 percent, and 7.9 percent, respectively.
The confidence interval (e.g., as calculated for Children ever born to women aged 15-49) can be interpreted as follows: the overall average from the national sample is 3.167 and its standard error is .042. Therefore, to obtain the 95 percent confidence limits, one adds and subtracts twice the standard error to the sample estimate, ie. 3.167+.084. There is a high probability (95 percent) that the true average number of children ever born to all women aged 15 to 49 is between 3.083 and 3.251.
Data Appraisal
Nonsampling error is the result of mistakes made in implementing data collection and data processing, such as failure to locate and interview the correct household, misunderstanding of the questions on the part of either the interviewer or the respondent, and data entry errors. Although numerous efforts were made during the implementation of the KDHS to minimize this type of error, nonsampling errors are impossible to avoid and difficult to evaluate statistically.
Access policy
Access authority
| Name | Affiliation | URL | |
|---|---|---|---|
| MEASURE DHS | ICF International | archive@measuredhs.com | www.measuredhs.com |
Contacts
| Name | URL | |
|---|---|---|
| General Inquiries | info@measuredhs.com | www.measuredhs.com |
| Data and Data Related Resources | archive@measuredhs.com | www.measuredhs.com |
| National Co-ordination Agency for Population & Development (NCPD) | http://www.ncapd-ke.org/ |
Citation requirements
Use of the dataset must be acknowledged using a citation which would include:
- the Identification of the Primary Investigator
- the title of the survey (including country, acronym and year of implementation)
- the survey reference number
- the source and date of download
- the Identification of the Primary Investigator
- the title of the survey (including country, acronym and year of implementation)
- the survey reference number
- the source and date of download
Disclaimer and copyrights
Disclaimer
The user of the data acknowledges that the original collector of the data, the authorized distributor of the data, and the relevant funding agency bear no responsibility for use of the data or for interpretations or inferences based upon such uses.
Metadata production
DDI Document ID
ddi-ken-datafirst-dhs-1993-v1
Producers
| Name | Affiliation | Role |
|---|---|---|
| DataFirst | University of Cape Town | Metadata Producer |
Date of Metadata Production
2012-03-22