The primary objective of the 2008 BAIS III was to update current information on the behavioral patterns of the populations aged 10-64 years and the HIV prevalence and incidence rates among those aged 18 months and above at national, district and sub-district level. This information will be used for continuous strategic prevention and national HIV program planning and future HIV and AIDS research.
Specifically, the survey was intended to provide:
i. current national HIV prevalence and incidence estimates among the population aged 18 months and above;
ii. indicative trends in sexual and preventive behavior among the population aged 10-64 years;
iii. a comparison between HIV rate, behavior, knowledge, attitude, and cultural factors that are associated with the epidemic with estimates derived from previous surveys; and
iv. information on demographic, socio-economic, housing and household members' conditions associated with and/or are determinants and consequences of the pandemic.
A related objective is to produce survey results in a timely manner and ensure that the data are disseminated to a wide audience of potential users in government and non-governmental organizations within and outside Botswana as part of facilitation of broader effort to strengthen strategies aimed at combating the disease.
Kind of Data
Sample survey data [ssd]
Version 02 of the AIDS Impact Survey III 2008 was updated in the following metadata fields: Description of scope, citation requirements, disclaimer and datasets were provided.
Producers and sponsors
Authoring entity/Primary investigators
Central Statistics Office (CSO)
Ministry of Finance and Development Planning
National AIDS Coordinating Agency (NACA)
The 2008 Botswana AIDS Impact Survey III (BAIS III) was designed to provide a comparison (trend) between HIV prevalence rate, behavior, knowledge, attitude, and other factors that are associated with the epidemic with estimates derived from previous survey, i.e. 2004 BAIS II.
For BAIS-II the sampling frame based on the 2001 Population and Housing Census. This comprised the list of all Enumeration Areas (EAs) together with number of households. In 2001 Census the EAs were framed of manageable size (in terms of dwellings/households). So, the primary sampling units (PSUs) were EAs.
Stratification was undertaken such that all districts and major urban centers become their own strata. With regard to increase precision consideration was also given to group EAs according to ecological zones in rural districts and according to income categories in cities/towns. Geographical stratification along ecological zones and income categories was expected to improve the accuracy of survey data in view that homogeneity of the variables within stratum was relatively high.
A stratified two-stage probability sample design was used for the selection of the sample.
The first stage was the selection of EAs as Primary Sampling Units (PSUs) selected with probability proportional to measures of size (PPS), where measures of size (MOS) were the number of households in the EA as defined by the 2001 Population and Housing Census. In all 459 EAs were selected with probability proportional to size.
At the second stage of sampling, the households were systematically selected from fresh list of occupied households prepared at the beginning of the survey's fieldwork (i.e. listing of households for the selected EAs). Overall 8,275 households were drawn systematically.
Note: See detailed sampling information in BAIS-III final report.
Once the data set was cleaned, sampling weights were applied to the data. Being a multistage design, it follows naturally that the sample selected at each stage represents (or is assumed to) the respective population. The fundamental assumption is that units selected at each stage were similar to those not selected, in respect of characteristics of interest. In the treatment of unit for the non-response the assumption that the responders were similar to non-respondents though should not be always taken for granted.
Sampling weights are equal to the inverse of the probability of selection. Therefore the sampling probabilities at first stage of selection of EAs including probabilities of selecting the households were used to calculate the design weights. Non response adjustments were also taken into considerations while calculating the final sampling weight.
Dates of Data Collection (YYYY/MM/DD)
Mode of data collection
Type of Research Instrument
The questionnaires are the primary recording documents of the survey. In the development of the questionnaires, along with the professionals, the other members (Including some users) were also invited. The final version of the questionnaires was finalized on the basis of the experiences aimed from the pretest conducted using the drafted questionnaires for the survey.
The 208 BAIS III has three major components, namely the Household Questionnaire, the Individual Questionnaire and the Blood Collection Form.
The Household Questionnaire was used to list all members of the selected households and their demographic characteristics such as age, sex, orphan hood (0-17 years) and economic activity.
The Individual Questionnaire was designed to capture information regarding demographic characteristics, care and support, marriage and cohabiting partnerships, alcohol consumption and drug use, sexual history and behavior, male circumcision and sexually transmitted diseases, knowledge about HIV/AIDS and level of interventions, attitudes towards people with HIV/AIDS, childbearing and antenatal care as well as availability of social and medical services in response to the pandemic.
The third component is on the scale of the pandemic. It was designed to collect blood samples from members of households aged 18 months and over for testing and estimation of HIV prevalence and derivation of incidence measures.
Before data entry was carried out, the questionnaires were edited to check if all the relevant questions have been responded to and coded according to the codes designed for the study. Editing and coding started in July 2007 and finished in February 2008. Data entry was carried out under the supervision of one programmer/supervisor. Consistency checks on the data set as per the computer edit specifications designed by the subject matter specialists were performed.
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
Central Statistics Office. AIDS Impact Survey III (AIS) 2008. Ref. BWA_2008_AIS-III_v01_M. Dataset downloaded from [URL] on [date].
Disclaimer and copyrights
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.
Central Statistics Office
Development Economics Data Group
The World Bank
Documentation of the DDI
Date of Production
Version 02 (December 2017)
Updates were made in the following metadata fields:
- Description of scope
- Citation requirements
- Datasets provided