Demographic and Health Survey 2006-2007 - Kingdom of Eswatini

Abstract
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The 2006-07 Swaziland Demographic and Health Survey (SDHS) is a nationally represe­ntative survey of 4,843 households, 4,987 women age 15-49, and 4,156 men age 15-49. The SDHS also included individual interviews with boys and girls age 12-14 and older adults age 50 and over. The survey of persons age 12-14 and age 50 and over was carried out in every other household selected in the SDHS. Interviews were completed for 459 girls and 411 boys age 12-14, and 661 women and 456 men age 50 and over.

The 2006-07 SDHS is the first national survey conducted in Swaziland as part of the De­mographic and Health Surveys (DHS) programme. The data are intended to furnish programme managers and policymakers with de­tailed information on levels and trends in fertility; nuptiality; sexual activity; fertility prefer­ences; awareness and use of family planning methods; breastfeeding practices; nutritional status of mothers and young children; early childhood mortality and maternal mortality; ma­ternal and child health; and awareness and behaviour regarding HIV/AIDS and other sexually transmitted infections. The survey also collected information on malaria prevention and treat­ment.

The 2006-07 SDHS is the first nationwide survey in Swaziland to provide population-based prevalence estimates for anaemia and HIV. Children age 6 months and older as well as adults were tested for anaemia. Children age 2 years and older as well as adults were tested for HIV.

The principal objective of the 2006-07 Swaziland Demographic and Health Survey (SDHS) was to provide up-to-date information on fertility, childhood mortality, marriage, fertility preferences, awareness, and use of family planning methods, infant feeding practices, maternal and child health, maternal mortality, HIV/AIDS-related knowledge and behaviour and prevalence of HIV and anaemia.

More specifically the 2006-07 SDHS was aimed at achieving the following;
- Determine key demographic rates, particularly fertility, under-five mortality, and adult mor­tality rates
- Investigate the direct and indirect factors which determine the level and trends of fertility
- Measure the level of contraceptive knowledge and practice of women and men by method
- Determine immunization coverage and prevalence and treatment of diarrhoea and acute res­piratory diseases among children under five
- Determine infant and young child feeding practices and assess the nutritional status of chil­dren 6-59 months, women age 15-49 years, and men aged 15-49 years
- Estimate prevalence of anaemia
- Assess knowledge and attitudes of women and men regarding sexually transmitted infections and HIV/AIDS, and evaluate patterns of recent behaviour regarding condom use
- Identify behaviours that protect or predispose the population to HIV infection
- Examine social, economic, and cultural determinants of HIV
- Determine the proportion of households with orphans and vulnerable children (OVCs)
- Determine the proportion of households with sick people taken care at household level
- Determine HIV prevalence among males and females age 2 years and older
- Determine the use of iodized salt in households
- Describe care and protection of children age 12-14 years, and their knowledge and attitudes about sex and HIV/AIDS.

This information is intended to provide data to assist policymakers and programme implementers to monitor and evaluate existing programmes and to design new strategies for demographic, social and health policies in Swaziland. The survey also provides data to monitor the country's achievement towards the Millenium Development Goals.

MAIN RESULTS

- Fertility in Swaziland has been declining ra­pidly, with the TFR falling from 6.4 births per woman in 1986 to 3.8 births at the time of the SDHS. As expected, fertility is higher in rural areas (4.2 births per woman) than in urban areas (3.0 births per woman). Fertility differentials by education and wealth are substantial. Women with no education have on average 4.9 children compared with 2.4 children for women with tertiary education. Fertility varies widely according to household wealth. Women in the highest wealth quintile have 2.9 chil­dren fewer than women in the lowest quintile (2.6 and 5.5 births per woman, respectively).

- Knowledge of family planning is universal in Swaziland. The most widely known method is the male condom (99 percent for both males and females). Among women, other widely known methods include injectables (96 percent), the pill (95 percent), and the female condom (91 per­cent). For men, the best known methods besides the male condom are the female condom (94 percent) and the pill and injectables (84 percent each).

- Children are considered fully vaccinated when they receive one dose of BCG vaccine, three doses each of DPT and polio vaccines, and one dose of measles vaccine. BCG coverage among children age 12-23 months is nearly uni­versal (97 percent); coverage is also high for the first doses of DPT (96 percent) and polio (97 percent). The proportion of children receiving subsequent do­ses of DPT and polio vaccines drops slightly, with 92 percent of children receiving the third dose of DPT and 87 percent receiving the third dose of polio. Ninety-two percent of children had received a mea­sles vaccination by the time of the SDHS. Overall, 82 percent of children age 12-23 months are fully im­munised.

- In Swaziland, almost all women who had a live birth in the five years preceding the survey received antenatal care from health professionals (97 percent); 9 percent received care from a doctor, and 88 percent received care from a trained nurse or midwife. Only 3 percent of mothers did not receive any antenatal care

- Overall, 87 percent of children in Swaziland are breastfed for some period of time (ever breastfed). The median duration of any breast-feeding in Swaziland is almost 17 months. How­ever, the median duration of exclusive breast-feeding is much shorter (0.7 months).

- In interpreting the malaria programme indicators in Swaziland, it is important to recognise that the dis­ease affects an estimated 30 percent of the population where malaria is most prevalent (the Lubombo Pla­teau, the lowveld, and parts of the middleveld). Malaria is also seasonal, occurring mainly during or after the rainy season (from November to March). A substantial part of the SDHS field­work took place outside of this period.

- Results from the HIV testing component in the 2006-07 SDHS indicate that 26 percent of Swazi adults age 15-49 are infected with HIV. Among women, the HIV rate is 31 percent, com­pared with 20 percent among men. HIV preva­lence peaks at 49 percent for women age 25-29, which is almost five times the rate among wo­men age 15-19 and more than twice the rate ob­served among women age 45-49. HIV preva­lence increases from 2 percent among men in the 15-19 age group to 45 percent in the age group 35-39 and then decreases to 28 percent among men age 45-49. HIV prevalence for women and men age 50 or over is 12 percent and 18 percent, respectively. Among the population age 2-14 years, 4 percent of girls and boys are infected.

Geographic coverage
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The 2006-07 Swaziland Demographic and Health Survey (SDHS) is a nationally represe­ntative survey. It was designed to provide estimates of health and demographic indicators at the national level, for urban-rural areas, and for the four regions of Manzini, Hhohho, Lubombo, and Shiselweni.

Analysis unit
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- Household
- Women age 15-49
- Men age 15-49
- Young adults age 12-14
- adults age 50 and over

Universe
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The population covered by the 2006 SWZDHS is defined as the universe of all women Ever-married women in the reproductive ages (i.e., women 15-49).

Kind of data
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Sample survey data

Sampling procedure
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The 2006-07 SDHS was designed to provide estimates of health and demographic indicators at the national level, for urban-rural areas, and for the four regions of Manzini, Hhohho, Lubombo, and Shiselweni. Standard DHS sampling policy recommends a minimum of 1,000 to 1,200 women per major domain. To meet this criterion, the number of households selected in each of the various domains, particularly urban areas, was not proportional to the actual size of the population in the domain. As a result, the SDHS sample is not self-weighting at the national level, and weights must be applied to the data to obtain the national-level estimates.

The 2006-07 SDHS sample points (clusters) were selected from a list of enumeration areas (EAs) defined in the 1997 Swaziland Population and Housing Census. A total of 275 clusters were drawn from the census sample frame, 111 in the urban areas and 164 in the rural areas.

CSO staff conducted an exhaustive listing of households in each of the SDHS clusters in August and September 2005. From these lists, a systematic sample of households was drawn for a total of 5,500 households. All women and men age 15-49 identified in these households were eligible for individual interview. In addition, a sub-sample of half of these households (2,750 households) was selected randomly in which all boys and girls age 12-14 and persons age 50 and older were eligible for individual interview. In the SDHS households where youth and older adults were interviewed, all individuals age 6 months and older were eligible for anaemia testing and all individuals age 2 and older were eligible for HIV testing. In the SDHS households where only women and men age 15-49 were interviewed, children age 6 months to 5 years were eligible for the anaemia testing and women and men age 15-49 were eligible for anaemia and HIV testing.

During the household listing, field staff used Global Positioning System (GPS) receivers to establish and record the geographic coordinates of each of the SDHS clusters.

Mode of data collection
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Face-to-face

Research instrument
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Five types of questionnaires were used for the SDHS: a) the Household Questionnaire, b) the Woman's Questionnaire, c) the Man's Questionnaire, d) the Youth Questionnaire, and the e) Older Adult Questionnaire. The contents of the questionnaires were based on questionnaires developed for the MEASURE DHS programme. The Youth Questionnaire was adapted from the 2002 Nelson Mandela/HSRC Study of HIV/AIDS in South Africa. The SDHS questionnaires were developed in collaboration with a wide range of stakeholders. After the SDHS survey instruments were drafted, they were translated into and printed in the local language, Siswati, for pretesting.

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. The Household Questionnaire was also used to identify persons eligible for the individual interview. In addition, information was collected about the dwelling, such as the source of water; type of toilet facilities; materials used to construct the house; ownership of various consumer goods; use of bed nets; and care and free external support received by chronically ill household members and orphans and vulnerable children. The results of anthropometric measurement and anaemia testing were recorded in the Household Questionnaire, as was the information on the consent of eligible household members for the HIV testing.

b) The Woman's Questionnaire was used to collect information from all women age 15-49 and covered the following topics:

- Background characteristics (age, education, religion, etc.)
- Birth history
- Knowledge and use of family planning methods
- Antenatal and delivery care
- Infant feeding practices including patterns of breastfeeding
- Vaccinations
- Childhood illnesses and treatment
- Marriage and sexual activity
- Fertility preferences
- Husband's background and woman's work status
- Adult (maternal) mortality
- HIV/AIDS-related knowledge, attitudes, and behaviour.

c) The Man's Questionnaire was shorter than the Woman's Questionnaire, but covered many of the same topics, excluding the reproductive history and sections dealing with maternal and child health.

d) The Older Adult Questionnaire obtained limited information on the background characteristics of the popu­lation age 50 and over and on HIV/AIDS knowledge, attitudes, and risk behaviour.

e) The Youth Question­naire included questions on knowledge and attitudes about sex, and factors exposing youth to risk of abuse.

Cleaning operations
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All questionnaires for the SDHS were returned to CSO central office for data processing. The processing operation consisted of office editing, coding of open-ended questions, data entry, double-entry verification, and resolving inconsistencies found by computer programmes developed for the SDHS. The SDHS data entry and editing programmes used CSPro, a computer software package specifically designed for processing survey data such as that produced by DHS surveys. Data processing commenced in August 2006 and was completed in April 2007.

The HIV testing was carried out at the NRL between August 2006 and June 2007.

Response rate
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The response rates are important because they may affect the reliability of the results. Of a total of 5,500 households selected in the sample, 5,086 were occupied at the time of the fieldwork. This difference between the number of selected households and the number of occupied households is due to structures being vacated or destroyed. Successful interviews were conducted in 4,843 households, yielding a response rate of 95 percent.

In the households interviewed in the survey, a total of 5,301 eligible women age 15-49 were identified. Interviews were completed with 4,987 of these women, yielding a 94 percent response rate. In the same households, a total of 4,675 eligible men age 15-49 were identified and interviews were com­pleted with 4,156 of these men, yielding a male response rate of 89 percent. The response rates are slightly lower in the urban sample than in the rural sample, and lower among men than women. The principal reasons for non-response among both eligible men and women were refusal and the failure to find individuals at home despite repeated visits to the households. Men have lower response rates than women due to higher refusal rates, and more frequent and longer absence from the households, principally due to employment and their lifestyle.

A total of 2,750 households were selected in the sample, of which 2,543 were occupied at the time of the fieldwork. This difference between the number of selected households and the number of occupied households is due to structures being vacated or destroyed. Successful interviews were conducted in 2,410 households, yielding a response rate of 95 percent.

In the households selected for the youth and older adult survey, a total of 477 eligible girls and 439 eligible boys age 12-14 were identified. Interviews were completed with 459 girls and 411 boys, yielding response rates of 96 percent and 94 percent, respectively. The response rates for girls are the same for urban and rural areas. For boys, the response rate is slightly lower in urban than in rural areas (89 percent compared with 94 percent).

A total of 693 eligible women age 50 and over were identified. Interviews were completed with 661 of these women, yielding a 95 percent response rate. In the same households, a total of 492 eligible men age 50 and over were identified and interviews were completed with 456 of these men, yielding a male response rate of 93 percent. The response rates are slightly lower in urban than in rural areas, and lower among men than women.

Sampling error estimates
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Sampling errors, on the other hand, can be evaluated statistically. The sample of respondents selected in the 2006-07 SDHS 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 2006-07 SDHS 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 2006-07 SDHS 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 2006-07 NDHS, there were 275 non-empty clusters. Hence, 275 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.

Sampling errors for the 2006-07 SDHS are calculated for selected variables considered to be of primary interest for woman's survey and for man's surveys, respectively. The results are presented in an appendix to the Final Report for the country as a whole, for urban and rural areas, and for each of the eleven regions. 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.8 present the value of the statistic (R), its standard error (SE), the number of unweighted (N-UNWE) and weighted (N-WEIG) 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). In the case of the total fertility rate, the number of unweighted cases is not relevant, as there is no known unweighted value for woman-years of exposure to child-bearing.

The confidence interval (e.g., as calculated for children ever born to women aged 40-49) can be interpreted as follows: the overall average from the national sample is 5.339 and its standard error is 0.118. Therefore, to obtain the 95 percent confidence limits, one adds and subtracts twice the standard error to the sample estimate, i.e., 5.339 ± 2 × 0.118. There is a high probability (95 percent) that the true average number of children ever born to all women aged 40 to 49 is between 5.103 and 5.575. Sampling errors are analyzed for two separate groups of estimates: (1) means and proportions, and (2) complex demographic rates. At the national level, mostly relative standard error values (SE/R) for the means and proportions are below 10 percent, however the highest relative standard error values are for indicators with very low values (i.e. less than 2 percent). So in general, the relative standard errors for most estimates for the country as a whole are small, except for indicators with very small values, i.e. for estimates which are rare in the population. For example, the relative standard error for the total fertility rate (TFR 0-3 years) is small (2.9 percent) since births are a fairly common event. However, for the mortality rates which are rarer events, the average relative standard error value is higher; for example, the relative standard error for the 0-4 year estimate of mortality rates is 9.4 percent. The relative standard error varies across sub-populations. For example, for the variable children ever born to women aged 40-49, the relative standard errors as a percent of the estimated mean for the whole country, for the urban areas and for the rural areas are 2.2 percent, 4.2 percent and 2.5 percent, respectively. For the total sample, the value of the design effect (DEFT), averaged over all selected variables, is 1.15 which means that, due to multi-stage clustering of the sample, the average standard error is increased by a factor of 1.15 over that in an equivalent simple random sample.

Data appraisal
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Non-sampling errors are the results 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 2006-07 Swaziland Demographic and Health Survey (SDHS) to minimize this type of error, non-sampling errors are impossible to avoid and difficult to evaluate statistically.

摘要
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2006-07 斯威士兰人口与健康调查（SDHS）是一项全国性代表性调查，涉及4,843个家庭，4,987名15-49岁的女性和4,156名15-49岁的男性。此外，调查还包含了12-14岁男孩和女孩以及50岁及以上成年人的个别访谈，这些访谈是在SDHS中每两户家庭中选择一户进行的。12-14岁的女孩和男孩共有459人和411人接受了访谈，50岁及以上的女性有661人，男性有456人。

2006-07 SDHS是斯威士兰作为人口与健康调查（DHS）项目的一部分进行的首次全国性调查。数据旨在为项目管理人员和政策制定者提供有关生育率、婚配率、性行为、生育偏好、计划生育方法的认识和使用、母乳喂养实践、母亲和婴幼儿的营养状况、婴幼儿死亡率和孕产妇死亡率、母亲和儿童健康、以及有关艾滋病/HIV和其他性传播感染的认识和行为的信息。调查还收集了有关疟疾预防和治疗的信息。

2006-07 SDHS是斯威士兰首次提供基于人口学的贫血和HIV患病率估计的全国性调查。6个月及以上儿童以及成年人接受了贫血测试。2岁及以上儿童以及成年人接受了HIV测试。

2006-07斯威士兰人口与健康调查（SDHS）的主要目标是提供有关生育率、儿童死亡率、婚姻、生育偏好、认识和使用计划生育方法、婴儿喂养实践、母亲和儿童健康、孕产妇死亡率、艾滋病/HIV相关知识和行为以及HIV和贫血患病率的最新信息。

更具体地说，2006-07 SDHS旨在实现以下目标：
- 确定关键的人口统计数据，尤其是生育率、5岁以下儿童死亡率和成年人死亡率
- 调查决定生育率水平和趋势的直接和间接因素
- 测量妇女和男人通过方法了解和使用避孕药具的程度
- 确定5岁以下儿童接种率、患病率和腹泻及急性呼吸道疾病的预防和治疗
- 确定婴幼儿喂养实践，并评估6-59个月儿童、15-49岁妇女和15-49岁男性的营养状况
- 估计贫血患病率
- 评估妇女和男人对性传播感染和HIV/AIDS的认识和态度，并评估近期避孕套使用行为的模式
- 确定保护或使人群易受HIV感染的行为
- 考察HIV的社会、经济和文化决定因素
- 确定孤儿和脆弱儿童（OVCs）家庭的比例
- 确定在家庭层面接受护理的患病人员的家庭比例
- 确定2岁及以上男性和女性的HIV患病率
- 确定家庭中使用碘盐的情况
- 描述12-14岁儿童的照顾和保护，以及他们关于性和HIV/AIDS的知识和态度。

这些信息旨在为政策制定者和项目实施者提供数据，以监测和评估现有项目，并设计斯威士兰人口、社会和健康政策的新战略。调查还提供了数据，以监测该国实现千年发展目标的情况。

主要结果
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- 斯威士兰的生育率一直在迅速下降，总生育率（TFR）从1986年的每名女性6.4个出生下降到SDHS时的3.8个出生。正如预期的那样，农村地区的生育率（每名女性4.2个出生）高于城市地区（每名女性3.0个出生）。教育水平和财富的生育差异很大。没有受过教育的妇女平均有4.9个孩子，而受过高等教育（专科教育）的妇女平均有2.4个孩子。生育率根据家庭财富而有很大差异。最高财富五分位数中的妇女比最低五分位数中的妇女少有2.9个孩子（分别为每名女性2.6个和5.5个出生）。

- 家庭计划的知识在斯威士兰是普遍的。最广为人知的方法是男性避孕套（男性和女性均为99％）。在妇女中，其他广为人知的方法包括注射剂（96％）、口服避孕药（95％）和女性避孕套（91％）。在男性中，除男性避孕套外，最知名的方法是女性避孕套（94％）、口服避孕药和注射剂（各84％）。

- 儿童在接种一剂BCG疫苗、DPT和脊髓灰质炎疫苗各三剂以及一剂麻疹疫苗后被认为是完全接种的。12-23个月大儿童的BCG接种率几乎为普遍（97％）；DPT第一剂（96％）和脊髓灰质炎（97％）的接种率也很高。接种DPT和脊髓灰质炎疫苗的后续剂量接种比例略有下降，其中92％的儿童接种了DPT的第三剂，87％的儿童接种了脊髓灰质炎的第三剂。到SDHS时，92％的儿童已接种了麻疹疫苗。总体而言，82％的12-23个月大儿童的接种率是完全的。

- 在斯威士兰，几乎所有在调查前五年内生育过活产儿的妇女都接受了从医务人员那里提供的产前护理（97％）；9％的人接受了医生的护理，88％的人接受了受过训练的护士或助产士的护理。只有3％的母亲没有接受任何产前护理。

- 在斯威士兰，87％的儿童在某个时期都进行过母乳喂养（曾经母乳喂养过）。斯威士兰母乳喂养的中位持续时间为近17个月。然而，纯母乳喂养的中位持续时间要短得多（0.7个月）。

- 在解释斯威士兰疟疾项目指标时，重要的是要认识到，该疾病影响了疟疾最普遍的估计有30％的人口（鲁邦多高原、低地和中高地）。疟疾也是季节性的，主要在雨季期间或之后发生（从11月到3月）。SDHS的实地工作有很大一部分是在这个时期之外进行的。

- 2006-07 SDHS中HIV检测部分的调查结果指出，26％的斯威士兰15-49岁成年人感染了HIV。在女性中，HIV患病率为31％，而男性为20％。HIV患病率在25-29岁的女性中达到49％，几乎是15-19岁女性的五倍，是45-49岁女性的两倍多。HIV患病率从15-19岁年龄组的2％增加到35-39岁年龄组的45％，然后下降到45-49岁男性的28％。50岁及以上的妇女和男性的HIV患病率分别为12％和18％。在2-14岁的人口中，4％的女孩和男孩感染了HIV。

地理覆盖范围
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2006-07斯威士兰人口与健康调查（SDHS）是一项全国性代表性调查。其设计目的是提供全国、城乡地区以及曼齐尼、赫霍霍、鲁邦多和希谢伦尼四个地区的健康和人口统计指标的估计值。

分析单元
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- 家庭
- 15-49岁妇女
- 15-49岁男性
- 12-14岁青年
- 50岁及以上成年人

总体
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2006年SWZDHS涵盖的人口定义为所有已婚、处于生育年龄（即15-49岁）的妇女的总体。

数据类型
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样本调查数据

抽样程序
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2006-07 SDHS旨在提供全国、城乡地区以及曼齐尼、赫霍霍、鲁邦多和希谢伦尼四个地区的健康和人口统计指标的估计值。标准DHS抽样政策建议每个主要领域至少有1,000到1,200名妇女。为了满足这一标准，每个不同领域（尤其是城市地区）选择的家庭数量并不与该领域实际人口规模成比例。因此，SDHS样本在全国层面上不是自我加权，必须对数据进行加权以获得全国层面的估计。

2006-07 SDHS样本点（集群）是从1997年斯威士兰人口与住房普查中定义的枚举区（EA）名单中选取的。从普查样本框架中抽取了275个集群，其中111个在城市地区，164个在农村地区。

CSO工作人员在2005年8月和9月对每个SDHS集群中的家庭进行了详尽的清单。从这些清单中，抽取了总共5,500个家庭的系统性样本。在所选家庭中识别的所有15-49岁的男性和女性都有资格进行个别访谈。此外，从这些家庭中随机选取了其中一半（2,750个家庭），其中所有12-14岁的男孩和女孩以及50岁及以上的人都有资格进行个别访谈。在SDHS家庭中，对青年和老年人进行访谈，所有6个月及以上的人都有资格进行贫血测试，所有2岁及以上的人都有资格进行HIV测试。在只对15-49岁的妇女和男性进行访谈的SDHS家庭中，6个月到5岁的儿童有资格进行贫血测试，15-49岁的妇女和男性有资格进行贫血和HIV测试。

在家庭清单期间，现场工作人员使用全球定位系统（GPS）接收器建立和记录每个SDHS集群的地理坐标。

数据收集方式
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面对面

研究工具
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SDHS使用了五种类型的问卷：a）家庭问卷，b）妇女问卷，c）男性问卷，d）青年问卷和e）老年人问卷。问卷的内容基于为MEASURE DHS项目开发的问卷。青年问卷是从2002年纳尔逊·曼德拉/HSRC南非HIV/AIDS研究改编的。SDHS问卷是与广泛的利益相关者合作开发的。在SDHS调查工具草案完成后，它们被翻译成当地语言斯瓦蒂语进行预测试。

a）家庭问卷用于列出所选家庭中的所有常住成员和访客。收集了关于列出的每个人的基本信息的详细信息，包括年龄、性别、教育程度和与家庭主人的关系。家庭问卷还用于确定有资格进行个别访谈的人。此外，还收集了有关住所的信息，例如水源；厕所设施类型；建造房屋使用的材料；各种消费品的所有权；蚊帐的使用；以及慢性病患者和孤儿及脆弱儿童获得的护理和免费外部支持。人体测量测量和贫血测试的结果记录在家庭问卷中，以及有关有资格的家庭成员同意进行HIV测试的信息。

b）妇女问卷用于收集所有15-49岁妇女的信息，涵盖了以下主题：
- 背景特征（年龄、教育、宗教等）
- 出生史
- 家庭计划方法的了解和使用
- 产前和分娩护理
- 婴儿喂养实践，包括母乳喂养模式
- 接种
- 儿童疾病和治疗
- 婚姻和性行为
- 生育偏好
- 丈夫的背景和妇女的工作状况
- 成人（孕产妇）死亡率
- 艾滋病/HIV相关知识和行为。

c）男性问卷的长度短于妇女问卷，但涵盖了许多相同的话题，不包括生殖史和涉及孕产妇和儿童健康的部分。

d）老年人问卷获取了50岁及以上人口背景特征和HIV/AIDS知识和风险行为的有限信息。

e）青年问卷包括有关性知识和态度以及使青年面临滥用风险的因素的问题。

清洗操作
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所有SDHS问卷都返回到CSO中央办公室进行数据处理。处理操作包括办公室编辑、开放式问题的编码、数据输入、双重输入验证以及解决由SDHS开发的计算机程序发现的矛盾。SDHS数据输入和编辑程序使用CSPro，这是一种专门为处理如DHS调查产生的调查数据而设计的计算机软件包。数据处理始于2006年8月，并于2007年4月完成。

HIV测试是在2006年8月至2007年6月期间在NRL进行的。

响应率
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响应率很重要，因为它们可能影响结果的可靠性。在样本中选定的5,500个家庭中，有5,086个在实地工作期间有人居住。所选家庭数量和有人居住的家庭数量之间的差异是由于结构被空置或被毁。在4,843个家庭中成功进行了访谈，响应率为95％。

在调查中采访的家庭中，共有5,301名有资格的15-49岁妇女被识别。完成了4,987名这些妇女的访谈，响应率为94％。在相同的家庭中，共有4,675名有资格的15-49岁男性被识别，并完成了4,156名这些男性的访谈，男性响应率为89％。响应率在城市样本中略低于农村样本，在男性中低于女性。男女非响应的主要原因分别是拒绝和尽管反复访问家庭但未能找到个人的失败。由于拒绝率较高以及更频繁和更长时间不在家庭中（主要是由于就业和生活方式），男性的响应率低于女性。

在样本中选定的家庭中，共有2,750个家庭被选中，其中2,543个在实地工作期间有人居住。所选家庭数量和有人居住的家庭数量之间的差异是由于结构被空置或被毁。在2,410个家庭中成功进行了访谈，响应率为95％。

在选定的青年和老年人调查家庭中，共有477名有资格的12-14岁女孩和439名有资格的12-14岁男孩被识别。完成了459名女孩和411名男孩的访谈，分别达到96％和94％的响应率。女孩的响应率在城乡地区相同。对于男孩，城市地区的响应率略低于农村地区（89％与94％相比）。

共有693名有资格的50岁及以上妇女被识别。完成了661名这些妇女的访谈，响应率为95％。在相同的家庭中，共有492名有资格的50岁及以上男性被识别，并完成了456名这些男性的访谈，男性响应率为93％。响应率在城市地区略低于农村地区，在男性中低于女性。

抽样误差估计
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另一方面，抽样误差可以通过统计方法进行评估。2006-07 SDHS中选定的受访者样本只是从同一人口中，使用相同的设计和预期规模可以选出的许多样本中的一种。这些样本中的每一个都会产生与实际选定的样本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指标。虽然差异程度并不完全清楚，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。标准误差可用于计算置信区间，在此区间内，可以合理地假设人口的真实值。

如果受访者样本被选为简单随机样本，就可以使用简单的公式来计算抽样误差。然而，2006-07 SDHS样本是多层分层设计的产物，因此有必要使用更复杂的公式。用于计算2006-07 SDHS抽样误差的计算机软件是ISSA抽样误差模块。该模块使用了泰勒线性化方法来估计调查估计的方差，这些估计是平均值或比例。使用重复复制法来估计更复杂的统计数据，如生育率和死亡率。

重复复制法从父样本的多次复制中推导出复杂率的估计，并使用简单的公式计算这些估计的标准误差。每次复制都考虑了除一个集群以外的所有集群在估计计算中的计算。因此，创建了伪独立的复制。在2006-07 NDHS中，有275个非空集群。因此，创建了275个复制。

除了标准误差之外，ISSA还为每个估计计算了设计效应（DEFT），它定义为使用给定样本设计计算的标准误差与如果使用简单随机样本将产生的标准误差之比。DEFT值为1.0表示样本设计与简单随机样本一样有效，而大于1.0的值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区间。

2006-07 SDHS的抽样误差为妇女调查和男性调查分别考虑的选定变量计算。结果在国家的最终报告中以附录的形式呈现，包括城市和农村地区，以及每个11个地区。对于每个变量，表B.1中的最终报告给出了统计量的类型（平均值、比例或率）和基数人口。表B.2至B.8呈现了统计量的值（R）、其标准误差（SE）、未加权（N-UNWE）和加权（N-WEIG）案例的数量、设计效应（DEFT）、相对标准误差（SE/R）和95％置信区间（R±2SE），对于每个变量。当考虑简单随机样本时的标准误差为零时，DEFT被认为是未定义的（当估计接近0或1时）。在总生育率的情况下，未加权案例的数量不相关，因为没有已知的未加权值，即没有已知的暴露于生育的妇女年数。

置信区间（例如，计算40-49岁妇女的生育过的孩子数量）可以这样解释：国家样本的总体平均值为5.339，其标准误差为0.118。因此，为了获得95％置信区间，将样本估计值加上和减去两倍的标准误差，即5.339±2×0.118。有很高的可能性（95％）表示所有40至49岁妇女的真正平均生育孩子数量在5.103至5.575之间。对两组估计进行了抽样误差分析：（1）平均值和比例，以及（2）复杂的人口统计数据。在全国层面上，大多数平均值和比例的相对标准误差值（SE/R）低于10％，然而，最高的相对标准误差值是对于非常低的指标（即小于2％）。因此，总的来说，大多数估计的相对标准误差对于整个国家来说都很小，除了非常小的指标，即对于在人口中很少见的估计。例如，总生育率（TFR 0-3年）的相对标准误差很小（2.9％），因为出生是一个相当普遍的事件。然而，对于更罕见的事件，如死亡率，平均相对标准误差值较高；例如，0-4岁死亡率估计的相对标准误差为9.4％。相对标准误差在不同子群体之间有所变化。例如，对于40-49岁妇女的生育过的孩子这一变量，相对标准误差作为全国估计平均值的百分比，对于城市地区和农村地区分别是2.2％、4.2％和2.5％。对于整个样本，所有选定变量的设计效应（DEFT）的平均值是1.15，这意味着由于样本的多阶段分层，平均标准误差比等效简单随机样本增加了1.15倍。

数据评估
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非抽样误差是由于在数据收集和处理中出现的错误而产生的结果，例如未能找到和采访正确的家庭、访谈员或受访者对问题的误解，以及数据输入错误。尽管在实施2006-07斯威士兰人口与健康调查（SDHS）期间做出了众多努力来最大限度地减少此类错误，但非抽样误差是不可能避免的，也很难从统计上进行评估。