Demographic and Health Survey 2003 - South Africa

Abstract
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The 2003 South African Demographic and Health Survey is the second national health survey to be conducted by the Department of Health, following the first in 1998. Compared with the first survey, the new survey has more extensive questions around sexual behaviour and for the first time included such questions to a sample of men. Anthropometric measurements were taken on children under five years, and the adult health module has been enhanced with questions relating to physical activity and micro-nutrient intake, important risk factors associated with chronic diseases. The 2003 SADHS has introduced a chapter reporting on the health, health service utilisation and living conditions of South Africa's older population (60 years or older) and how they have changed since 1998. This has been introduced because this component of the population is growing at a much higher rate than the other age groups. The chapter on adolescent health in 1998 focussed on health risk-taking behaviours of people aged 15-19 years. The chapter has been extended in the 2003 SADHS to include indicators of sexual behaviour of youth aged 15-24 years.

A total of 10 214 households were targeted for inclusion in the survey and 7 756 were interviewed, reflecting an 85 percent response rate. The survey comprised a household schedule to capture basic information about all the members of the household, comprehensive questionnaires to all women aged 15-49, as well as anthropometry of all children five years and younger. In every second household, interviews of all men 15-59 were conducted and in the alternate households, interviews and measurements of all adults 15 years and older were done including heights, weights, waist circumference, blood pressure and peak pulmonary flow. The overall response rate was 75 percent for women, 67 percent for men, 71 percent for adults, and 84 percent for children. This is slightly lower than the overall response rate for the 1998 SADHS, but varied substantially between provinces with a particularly low response rate in the Western Cape.

OBJECTIVES

In 1995 the National Health Information System of South Africa (NHIS/SA) committee identified the need for improved health information for planning services and monitoring programmes. The first South African Demographic and Health Survey (SADHS) was planned and implemented in 1998. At the time of the survey it was agreed that the survey had to be conducted every five years to enable the Department of Health to monitor trends in health services.

Information on a variety of demographic and health indicators were collected. The results of these surveys are intended to assist policy makers and programme managers in evaluating and designing programmes and strategies for improving health services in the country. In addition to the aspects covered in the 1998 SADHS, information on the following additional aspects was included in the 2003 SADHS:
- Information on children living in households where the biological mother is not staying in the household i.e. mother is dead, etc.
- Child anthropometric data
- Information on reproductive health and sexual behaviour of men
- Information on malaria
- Information on pensions/grants received by members of the household.

The primary objective of the 2003 SADHS was to provide up-to-date information on:
- Characteristics of households and respondents
- Fertility
- Contraception and fertility preferences
- Sexual behaviour, HIV and AIDS
- Infant and child mortality
- Maternal and child health
- Infant and child feeding
- Adolescent health
- Mortality and morbidity in adults
- Utilisation of health services
- Adult health: hypertension, chronic pulmonary disease and Asthma
- Risk factors for chronic diseases
- Oral health
- Health of older persons

STUDY LIMITATIONS AND RECOMMENDATIONS

Comparison of the socio-demographic characteristics of the sample with the 2001 Population Census shows an over-representation of urban areas and the African population group, and an under-representation of whites and Indian females. It also highlights many anomalies in the ages of the sample respondents, indicating problems in the quality of the data of the 2003 survey. Careful analysis has therefore been required to distinguish the findings that can be considered more robust and can be used for decision making. This has involved considering the internal consistency in the data, and the extent to which the results are consistent with other studies.

Some of the key demographic and adult health indicators show signs of data quality problems. In particular, the prevalence of hypertension, and the related indicators of quality of care are clearly problematic and difficult to interpret. In addition, the fertility levels and the child mortality estimates are not consistent with other data sources. The data problems appear to arise from poor fieldwork, suggesting that there was inadequate training, supervision and quality control during the implementation of the survey. It is imperative that the next SADHS is implemented with stronger quality control mechanisms in place. Moreover, consideration should be given to the frequency of future surveys. It is possible that the SADHS has become overloaded - with a complex implementation required in the field. Thus it may be appropriate to consider a more frequent survey with a rotation of modules as has been suggested by the WHO.

Geographic coverage
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The SADHS sample was designed to be a nationally representative probability sample of approximately 10000 households. The country was stratified into the nine provinces and each province was further stratified into urban and non-urban areas.

Analysis unit
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- Household
- Women age 15-49
- Men age 15-59
- Children under six years

Universe
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The population covered by the 2003 SADHS is defined as the universe of all women age 15­-49, all men 15-59 in South Africa.

Kind of data
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Sample survey data

Sampling procedure
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The SADHS sample was designed to be a nationally representative probability sample of approximately 10000 households. The country was stratified into the nine provinces and each province was further stratified into urban and non-urban areas.

The sampling frame for the SADHS was provided by Statistics South Africa (Stats SA) based on the enumeration areas (EAs) list of approximately 86000 EAs created during the 2001 census. Since the Indian population constitutes a very small fraction of the South African population, the Census 2001 EAs were stratified into Indian and non-Indian. An EA was classified as Indian if the proportion of persons who classified themselves as Indian during Census 2001 enumeration in that EA was 80 percent or more, otherwise it was classified as Non-Indian. Within the Indian stratum, EAs were sorted descending by the proportion of persons classified as Indian. It should be noted that some provinces and non-urban areas have a very small proportion of the Indian population hence the Indian stratum could not be further stratified by province or urban/non-urban. A sample of 1000 households was allocated to the stratum. Probability proportional to size (PPS) systematic sampling was used to sample EAs and the proportion of Indian persons in an EA was the measure of size. The non-Indian stratum was stratified explicitly by province and within province by the four geo types, i.e. urban formal, urban informal, rural formal and tribal. Each province was allocated a sample of 1000 households and within province the sample was proportionally allocated to the secondary strata, i.e. geo type. For both the Indian and Non-Indian strata the sample take of households within an EA was sixteen households. The number of visited households in an EA as recorded in the Census 2001, 09 Books was used as the measure of size (MOS) in the Non-Indian stratum.

The second stage of selection involved the systematic sampling of households/stands from the selected EAs. Funds were insufficient to allow implementation of a household listing operation in selected EAs. Fortunately, most of the country is covered by aerial photographs, which Statistics SA has used to create EA-specific photos. Using these photos, ASRC identified the global positioning system (GPS) coordinates of all the stands located within the boundaries of the selected EAs and selected 16 in each EA, for a total of 10080 selected. The GPS coordinates provided a means of uniquely identifying the selected stand. As a result of the differing sample proportions, the SADHS sample is not self-weighting at the national level and weighting factors have been applied to the data in this report.

A total of 630 Primary Sampling Units (PSUs) were selected for the 2003 SADHS (368 in urban areas and 262 in non-urban areas). This resulted in a total of 10214 households being selected throughout the country1. Every second household was selected for the adult health survey. In this second household, in addition to interviewing all women aged 15-49, all adults aged 15 and over were eligible to be interviewed with the adult health questionnaire. In every alternate household selected for the survey, not interviewed with the adult health questionnaire, all men aged 15-59 years were also eligible to be interviewed. It was expected that the sample would yield interviews with approximately 10000 households, 12500 women aged 15-49, 5000 adults and 5000 men.

Mode of data collection
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Face-to-face

Research instrument
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The survey utilised five questionnaires: a Household Questionnaire, a Women's Questionnaire, a Men's Questionnaire, an Adult Health Questionnaire and an Additional Children Questionnaire. The contents of the first three questionnaires were based on the DHS Model Questionnaires. These model questionnaires were adapted for use in South Africa during a series of meetings with a Project Team that consisted of representatives from the National Department of Health, the Medical Research Council, the Human Sciences Research Council, Statistics South Africa, National Department of Social Development and ORCMacro. Draft questionnaires were circulated to other interested groups, e.g. such as academic institutions. The Additional Children and Men's Questionnaires were developed to address information needs identified by stakeholders, e.g. information on children who were not staying with their biological mothers. All questionnaires were developed in English and then translated in all 11 official languages in South Africa (English, Afrikaans, isiXhosa, isiZulu, Sesotho, Setswana, Sepedi, SiSwati, Tshivenda, Xitsonga and isiNdebele).

a) The Household Questionnaire was used to list all the usual members and visitors in the selected households. Basic information was collected on the characteristics of each person listed, including age, sex, education and relationship to the head of the household. Information was collected about social grants, work status and injuries experienced in the last month. An important purpose of the Household Questionnaire was to identify women, men and adults who were eligible for individual interviews. In addition information was collected about the dwelling itself, such as the source of water, type of toilet facilities, material used to construct the house and ownership of various consumer goods.

b) The Women's Questionnaire was used to collect information from women aged 15-49 in all households. These women were asked questions on the following topics:

- Background characteristics (age, education, race, residence, marital status, etc.)
- Reproductive history
- Knowledge and use of contraceptive methods
- Antenatal, delivery, and postnatal care
- Breastfeeding and weaning practices
- Child health and immunisation
- Marriage and recent sexual activity
- Fertility preferences
- Adult and maternal mortality
- Knowledge of HIV and AIDS
- Husband's background and respondent's work

c) In every second household, all men and women aged 15 and above were eligible to be interviewed with the Adult Health Questionnaire. The respondents were asked questions on:
- Recent utilisation of health services, family medical history,
- Clinical conditions
- Dental health
- Occupational health
- Medications taken
- Habits and lifestyles
- Anthropometric measurements, and
- Blood pressure and lung function test.

d) In every second household in addition to the women, all men aged 15-59 were eligible to be interviewed. The Men's Questionnaire collected similar information contained in the Woman's Questionnaire but was shorter because it did not contain questions on reproductive history, maternal and child health, nutrition, and maternal mortality. Men were asked questions on the following topics:
- Husband's background and respondent's work
- Knowledge and use of contraceptive methods
- Antenatal, delivery, and postnatal care
- Breastfeeding and weaning practices
- Marriage and recent sexual activity
- Fertility preferences
- Adult mortality
- Knowledge of HIV and AIDS

e) In households in which there was a child under six years of age whose biological mother was either not alive or did not live in the household, information about the child was collected from a guardian using the Additional Child's Questionnaire. The level of child fostering is relatively high in South Africa and data on children's health collected only from biological mothers might be incomplete.

The SADHS questionnaires were pre-tested (in two languages) in July 2003, using the “behind the glass”2 technique. The questionnaires were then adapted to take into account the suggested changes for questions that were misunderstood or were not clear. Subsequently four teams of interviewers (one for each of four main language groups) were formed; the household, male, female and adult health questionnaires were tested in 4 identified areas. The lessons learnt from the two exercises were used to finalise the survey instruments. The questions were translated and produced in all official languages in South Africa (English, Afrikaans, isiXhosa, isiZulu, Sesotho, Setswana, Sepedi, SiSwati, TshiVenda, Xitsonga and isiNdebele)

Cleaning operations
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A preliminary round of data processing of the SADHS questionnaires was started in November 2003 so as to provide some feedback to field teams. The actual data processing did not start until January 2004, after a contract was arranged with the HSRC in Pretoria. Completed questionnaires were returned periodically from the field to ASRC, which in turn submitted them to HSRC, where they were entered and edited by data processing personnel specially trained for this task. Data were entered using programmes written in CSPro by ORC Macro. All data were entered twice (100 percent verification). The data processing of the survey was completed in October 2004.

Response rate
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Of the total 630 PSUs that were selected, fieldwork was not implemented in nine PSUs. The data file contained information for a total of 621 PSUs. A total of 10214 households were selected for the sample and 7756 were successfully interviewed. The shortfall was primarily due to refusals and to dwellings that were vacant or in which the inhabitants had left for an extended period at the time they were visited by interviewing teams. Of the 9181 households occupied 85 percent were successfully interviewed. In these households, 7966 women were identified as eligible for the individual women's interview (15-49) and interviews were completed with 7041 or 88 percent of them. In the one half of the households that were selected for inclusion in the adult health survey 9614 eligible adults age 15 and over were identified of which 8115 or 84 percent were interviewed. In the other half of the households that were selected for the men's questionnaire to be completed 3930 eligible men aged 15-59 were identified of which 3118 or 79 percent were interviewed. The principal reason for non-response among eligible women and men was the failure to find them at home despite repeated visits to the household.

Sampling error estimates
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The sample of respondents selected in the 2003 SADHS 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. Sampling errors are 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.

A 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 SADHS sample is the result of a multi-stage stratified design, and, consequently, it was necessary to use more complex formulae. The computer software used to calculate sampling errors for the 2003 SADHS is the ISSA Sampling Error Module. This module used the Taylor linearization method of variance estimation for survey estimates that are means or proportions. The Jackknife repeated replication method is used for variance estimation of more complex statistics such as fertility and mortality rates.

The Jackknife repeated replication method derives estimates of complex rates from each of several replications of the parent sample, and calculates standard errors for these estimates using simple formulae. Each replication considers all but one cluster in the calculation of the estimates. Pseudo-independent replications are thus created. In the SADHS, there were 621 non-empty clusters. Hence, 621 replications were created.

In addition to the standard error, ISSA 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. ISSA also computes the relative error and confidence limits for the estimates. In the case of indicators from the adult health module, SAS has been used to calculate these parameters.

Sampling errors for the 2003 SADHS are calculated for a few 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 and for urban and rural areas and for each province. For each variable, the type of statistic (mean, proportion, or rate) and the base population are given in Table B.1 of the Final Report. Tables B.2 to B.13 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. The DEFT is considered undefined when the standard error considering simple random sample is zero (when the estimate is close to 0 or 1).

The confidence interval (e.g., as calculated for had an HIV test and received results in the 12 months preceding the survey) can be interpreted as follows: the overall average from the national sample is 8.5 percent for women and its standard error is 0.005. Therefore, to obtain the 95 percent confidence limits, one adds and subtracts twice the standard error to the sample estimate, i.e., 0.085±2×0.005. There is a high probability (95 percent) that the true proportion of women age 15-49 in South Africa who had an HIV test and received the results in the 12 months prior to the survey is between 7.5 and 9.5 percent.

The relative standard errors (SE/R) for women at the national level range between 0.5 percent and 12.5 percent; the highest relative standard errors are for estimates of very low values (e.g., Had two or more sexual partners in last 12 months). In general, the relative standard error for most estimates for the country as a whole is small, except for estimates of very small proportions. Sampling errors are higher for subpopulations, e.g., urban and rural, than they are for the national population as a whole.
For the total sample, the value of the design effect (DEFT) for women at the national level, averaged over all variables is 1.36, which means that, due to multi-stage clustering of the sample, the average standard error is increased by a factor of 1.36 over that in an equivalent simple random sample.

摘要
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2003年南非人口与健康状况调查是继1998年首次调查之后的第二次全国性健康调查。与首次调查相比，新的调查在性行为方面提出了更广泛的问题，并首次对男性样本进行了此类问题的调查。对五岁以下儿童进行了人体测量学测量，并将成人健康模块扩展到包含与身体活动和微量营养素摄入相关的问题，这些都是与慢性病相关的重要风险因素。2003年南非人口与健康状况调查引入了关于南非60岁及以上老年人口的健康、医疗服务利用和生活状况的报告章节，以及自1998年以来的变化情况。这一章节的引入是因为这一人口群体增长速度远高于其他年龄群体。1998年关于青少年健康的章节专注于15至19岁人群的健康风险行为。在2003年南非人口与健康状况调查中，这一章节被扩展，包括15至24岁青年性行为的指标。

总计10,214户家庭被纳入调查范围，其中7,756户接受了调查，反映了85%的响应率。调查包括家庭日程安排，以捕捉关于家庭所有成员的基本信息，以及针对所有15至49岁女性的全面问卷，以及所有五岁以下儿童的体格测量。在每第二个家庭中，对所有15至59岁的男性进行了调查，而在另一个家庭中，对15岁及以上的所有成年人（包括身高、体重、腰围、血压和肺峰流量）进行了调查和测量。总体响应率为女性75%，男性67%，成年人71%，儿童84%。这略低于1998年南非人口与健康状况调查的总体响应率，但在各省之间差异很大，尤其是西开普省的响应率特别低。

目标
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1995年，南非国家卫生信息系统（NHIS/SA）委员会确定了改进健康信息以满足服务规划和项目监控需求的必要性。1998年计划并实施了第一次南非人口与健康状况调查（SADHS）。在调查时，一致认为该调查必须每五年进行一次，以便卫生部门能够监控卫生服务趋势。

收集了关于各种人口和健康指标的信息。这些调查的结果旨在帮助政策制定者和项目管理者评估和设计改善国家卫生服务的计划和策略。除了1998年南非人口与健康状况调查中涵盖的方面外，2003年南非人口与健康状况调查还包括以下附加信息：
- 关于生物母亲不在家庭中居住的儿童的信息，即母亲已故等情况。
- 儿童体格测量数据。
- 关于男性生殖健康和性行为的信息。
- 关于疟疾的信息。
- 关于家庭成员收到的养老金/补助的信息。

2003年南非人口与健康状况调查的主要目标是提供以下方面的最新信息：
- 家庭和受访者的特征
- 生育率
- 避孕和生育偏好
- 性行为、HIV和艾滋病
- 婴儿和儿童死亡率
- 妇幼健康
- 婴儿和儿童喂养
- 青少年健康
- 成人死亡率和发病率
- 卫生服务利用
- 成人健康：高血压、慢性肺病和哮喘
- 慢性病风险因素
- 口腔健康
- 老年人健康

研究限制和建议
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与2001年人口普查中样本的社会人口学特征的比较表明，城市地区和非洲人口群体被过度代表，而白人和印度女性被代表性不足。它还突出了样本受访者年龄中的许多异常，表明2003年调查数据质量存在问题。因此，需要进行仔细的分析，以区分那些可以被认为是更稳健的，并可用于决策的发现。这包括考虑数据的内部一致性以及结果与其他研究的相符程度。

一些关键的人口和成人健康指标显示出数据质量问题的迹象。特别是，高血压的患病率和相关护理质量指标显然存在问题，难以解释。此外，生育率和儿童死亡率估计与其他数据来源不一致。数据问题似乎源于现场工作质量低下，表明在调查实施期间存在培训、监督和质量控制不足。因此，必须确保下一次南非人口与健康状况调查的实施具有更强的质量控制机制。此外，应考虑未来调查的频率。可能的情况是，南非人口与健康状况调查已经超负荷——在实地实施复杂的实施。因此，可能有必要考虑一种更频繁的调查，如世界卫生组织所建议的，以模块轮换的方式进行。

地理覆盖范围
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南非人口与健康状况调查样本被设计为大约10,000户家庭的全国代表性概率样本。国家被划分为九个省份，每个省份进一步划分为城市和非城市地区。

分析单位
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- 家庭
- 15至49岁的女性
- 15至59岁的男性
- 六岁以下儿童

总体
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2003年南非人口与健康状况调查涵盖的人口是所有15至49岁的女性，所有15至59岁的南非男性。

数据类型
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样本调查数据

抽样程序
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南非人口与健康状况调查样本被设计为大约10,000户家庭的全国代表性概率样本。国家被划分为九个省份，每个省份进一步划分为城市和非城市地区。

南非人口与健康状况调查的抽样框架由南非统计局（Stats SA）根据2001年人口普查期间创建的大约86,000个人口普查区域（EAs）名单提供。由于印度人口在南非人口中占很小一部分，2001年人口普查的EAs被划分为印度和非印度。如果一个EAs中在2001年人口普查登记时自称为印度人的比例达到80%或更高，则该EAs被划分为印度人；否则，它被划分为非印度人。在印度层中，EAs按自称为印度人的比例降序排列。应注意，一些省份和非城市地区印度人口比例很小，因此印度层不能进一步按省份或城市/非城市进行分层。该层分配了1,000户家庭的样本。概率成比例大小（PPS）系统抽样用于抽样EAs，一个EAs中印度人的比例是大小的衡量标准。非印度层明确按省份分层，并在省份内部按四种地理类型进行分层，即城市正式、城市非正式、农村正式和部落。每个省份分配了1,000户家庭的样本，在省份内部，样本按比例分配到二级层，即地理类型。对于印度和非印度层，一个EAs中的家庭抽样量是16户。在2001年人口普查的09册中记录的每个EAs访问的家庭数量被用作非印度层中的大小（MOS）的衡量标准。

第二阶段的选择涉及从选定的EAs中系统抽样家庭/地块。由于资金不足，无法在选定的EAs中实施家庭登记操作。幸运的是，大多数国家都有航空照片，南非统计局已使用这些照片创建了特定于EAs的照片。使用这些照片，ASRC确定了所有位于选定EAs边界内的地块的全局定位系统（GPS）坐标，并在每个EAs中选择了16个，总共选择了10,080个。GPS坐标提供了一种唯一识别选定地块的方法。由于样本比例的不同，南非人口与健康状况调查样本在国家层面不是自我加权的，因此在此报告中应用了加权因子。

总共选择了630个一级抽样单位（PSU）用于2003年南非人口与健康状况调查（城市地区368个，非城市地区262个）。这导致在全国范围内共选择了10,214户家庭。每第二个家庭被选为成人健康调查。在这个第二个家庭中，除了对所有15至49岁的女性进行访谈外，所有15岁及以上的成年人都有资格接受成人健康问卷的访谈。在每个选定的调查家庭中，未接受成人健康问卷的调查，所有15至59岁的男性都有资格接受访谈。

数据收集方式
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面对面

研究工具
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调查使用了五份问卷：家庭问卷、女性问卷、男性问卷、成人健康问卷和额外儿童问卷。前三份问卷的内容基于DHS模型问卷。这些模型问卷在由国家卫生部门、医学研究委员会、人文科学研究所、南非统计局、国家社会发展部门和ORCMacro代表的项目团队的一系列会议期间进行了修改，以适应南非的使用。草拟问卷被分发给其他感兴趣的群体，例如学术机构。额外的儿童和男性问卷是为了解决利益相关者确定的信息需求而开发的，例如关于未与生物学母亲同住儿童的信息。所有问卷均用英语编写，然后翻译成南非所有11种官方语言（英语、阿非利堪斯语、isiXhosa、isiZulu、Sesotho、Setswana、Sepedi、SiSwati、Tshivenda、Xitsonga和isiNdebele）。

a) 家庭问卷用于列出选定家庭中所有常住成员和访客。收集了有关列出的每个人特征的基本信息，包括年龄、性别、教育和与家庭首脑的关系。收集了有关社会补助、工作状况和上个月经历的伤害的信息。家庭问卷的一个重要目的是确定有资格接受单独访谈的女性、男性和成年人。此外，还收集了有关住宅本身的信息，例如水源、厕所设施类型、房屋建造材料和各种消费品的所有权。

b) 女性问卷用于收集所有家庭中15至49岁女性的信息。这些女性被问及以下主题：
- 背景特征（年龄、教育、种族、居住地、婚姻状况等）
- 生殖史
- 关于避孕方法的了解和使用
- 产前、分娩和产后护理
- 喂养和断奶实践
- 儿童健康和免疫
- 婚姻和最近性活动
- 生育偏好
- 成人和孕产妇死亡率
- 关于HIV和艾滋病的了解
- 丈夫的背景和受访者的工作

c) 在每第二个家庭中，所有15岁及以上的男性和女性都有资格接受成人健康问卷的访谈。受访者被问及以下问题：
- 最近利用卫生服务、家族医疗史
- 临床状况
- 口腔健康
- 职业健康
- 服用的药物
- 习惯和生活方式
- 人体测量学测量
- 血压和肺功能测试

d) 在每个选定的调查家庭中，除了女性外，所有15至59岁的男性都有资格接受访谈。男性问卷收集了与女性问卷中包含的类似信息，但更短，因为它不包含关于生殖史、孕产妇健康、营养和孕产妇死亡率的问题。男性被问及以下主题：
- 丈夫的背景和受访者的工作
- 关于避孕方法的了解和使用
- 产前、分娩和产后护理
- 喂养和断奶实践
- 婚姻和最近性活动
- 生育偏好
- 成人死亡
- 关于HIV和艾滋病的了解

e) 在有六岁以下儿童的家庭中，如果该儿童生物学母亲已去世或未住在家庭中，则使用额外儿童问卷从监护人那里收集有关该儿童的信息。南非的儿童抚养率相对较高，仅从生物学母亲那里收集儿童健康数据可能是不完整的。

南非人口与健康状况调查问卷于2003年7月进行了预测试（使用两种语言），采用了“玻璃后”技术。然后，根据对误解或不够清楚的问题的建议更改，对问卷进行了调整。随后，组建了四个访谈员团队（每个主要语言组一个）；在4个确定的地区对家庭、男性、女性和成人健康问卷进行了测试。从这两项练习中吸取的教训被用于最终确定调查工具。问题被翻译并生产成南非所有官方语言（英语、阿非利堪斯语、isiXhosa、isiZulu、Sesotho、Setswana、Sepedi、SiSwati、TshiVenda、Xitsonga和isiNdebele）。

清理操作
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2003年11月开始了南非人口与健康状况调查问卷的初步数据处理，以便为现场团队提供一些反馈。实际的数据处理直到2004年1月才开始，因为与比勒陀利亚的HSRC安排了合同。完成的问卷定期从现场返回到ASRC，ASRC随后将它们提交给HSRC，在那里由专门为此任务接受培训的数据处理人员输入和编辑。数据使用由ORC Macro编写的CSPro程序输入。所有数据都输入了两次（100%验证）。调查的数据处理于2004年10月完成。

响应率
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在总共630个选定的PSU中，在9个PSU中没有实施现场工作。数据文件包含有关621个PSU的信息。总共选择了10,214户家庭作为样本，其中7,756户成功接受了调查。缺额主要是由于拒绝以及访问时住宅空置或居民已长期离开的情况。在9,181户被占领的家庭中，85%成功接受了调查。在这些家庭中，确定了7,966名有资格接受单独女性访谈（15-49岁）的女性，并对其中7041名或88%的女性进行了访谈。在选定的家庭中，其中一半被选入成人健康调查，确定了9614名有资格的15岁及以上的成年人，其中8,115名或84%接受了访谈。在选定的其他一半家庭中，选定了男性问卷以完成调查，确定了3,930名有资格的15至59岁的男性，其中3,118名或79%接受了访谈。有资格的女性和男性未响应的主要原因是在多次访问家庭后未能找到他们。

抽样误差估计
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2003年南非人口与健康状况调查中选定的受访者样本只是从同一人口中选出的许多可能样本中的一种，使用相同的设计和预期规模。每个这样的样本都会产生与实际选定样本的结果略有不同的结果。抽样误差是衡量所有可能样本之间差异的一个指标。尽管变异的程度不完全清楚，但可以从调查结果中估计出来。

抽样误差通常以特定统计量（平均值、百分比等）的标准误差来衡量，这是方差的平方根。标准误差可以用来计算置信区间，在这个区间内可以合理地假设总体中真实值的范围。例如，对于从样本调查中计算出的任何给定统计量，该统计量的值将在95%的所有可能样本中相同大小和设计的情况下，正负两个标准误差的范围内。

如果受访者样本被选为简单随机样本，则可以使用简单的公式来计算抽样误差。然而，南非人口与健康状况调查样本是多层次分层设计的产物，因此有必要使用更复杂的公式。用于计算2003年南非人口与健康状况调查抽样误差的计算机软件是ISSA抽样误差模块。该模块使用泰勒线性化方法估计调查估计的方差，这些估计是平均值或比例。用于更复杂的统计量（如生育率和死亡率）的方差估计使用Jackknife重复复制方法。

Jackknife重复复制方法从父样本的多次复制中得出复杂率的估计，并使用简单的公式计算这些估计的标准误差。每次复制考虑了在估计计算中所有但一个集群。因此创建了伪独立复制。在南非人口与健康状况调查中，有621个非空集群。因此，创建了621次复制。

除了标准误差外，ISSA还为每个估计计算了设计效应（DEFT），该效应定义为使用给定样本设计计算的标准误差与使用简单随机样本将产生的结果之间的比率。DEFT值为1.0表示样本设计与简单随机样本一样高效，而值大于1.0表示由于使用更复杂且统计效率较低的样本设计而增加的抽样误差。ISSA还计算了估计的相对误差和置信限。

2003年南非人口与健康状况调查的抽样误差针对几个被认为是最感兴趣的变量进行了计算。结果在最终报告的附录中按国家整体、城市和农村地区以及每个省份进行了说明。对于每个变量，表中B.1给出了统计量类型（平均值、比例或比率）和基人口。表B.2至B.13显示了统计量的值（R）、标准误差（SE）、未加权（N）和加权（WN）案例的数量、设计效应（DEFT）、相对标准误差（SE/R）和95%置信限（R±2SE），对于每个变量。

置信区间（例如，对于在调查前12个月内进行了HIV检测并收到结果的情况）可以解释如下：国家样本的总体平均值为8.5%，其标准误差为0.005。因此，为了获得95%置信限，将样本估计值加上和减去两次标准误差，即0.085±2×0.005。有很高的可能性（95%）表明，在调查前12个月内进行了HIV检测并收到结果的南非15至49岁女性的真实比例在7.5%至9.5%之间。

国家层面的女性相对标准误差（SE/R）介于0.5%至12.5%之间；最高相对标准误差是针对估计非常低值的估计（例如，在过去12个月内有两个或更多性伴侣）。一般来说，对于整个国家的估计，相对标准误差很小，除了非常小的比例的估计。对于子人口（例如，城市和农村）的抽样误差高于国家总人口。

对于整个样本，国家层面的女性设计效应（DEFT）在所有变量上的平均值是1.36，这意味着由于样本的多阶段聚类，平均标准误差比等效简单随机样本增加了1.36倍。