Demographic and Health Survey 2009
Samoa, 2009
Identification
WSM_2009_DHS_v01_M
Demographic and Health Survey 2009
| Name | Country code |
|---|---|
| Samoa | WSM |
Demographic and Health Survey (standard) - DHS V
The 2009 SDHS is the first DHS survey to be undertaken in Samoa both by the health sector and for an improved health system.
The 2009 Samoa Demographic and Health Survey (2009 SDHS) is a nationally representative sample survey designed to provide information on population and health issues in Samoa. The survey used a two-stage sample based on the 2006 Population and Housing Census (PHC) to produce separate estimates for key indicators for each of the four geographic regions in Samoa. Each household selected for the SDHS was eligible for interview with the Household Questionnaire, and a total of 2,247 households were interviewed. In all of the households selected for the survey, all eligible women age 15-49 were interviewed with the Women's Questionnaire. In addition, all eligible men age 15-54 in every other household (half of all households) selected for the survey were interviewed with the Men's Questionnaire. A total of 3,033 women age 15-49 and 1,689 men age 15-54 were interviewed. Data collection took place from early August to early September 2009.
The survey obtained detailed information on fertility, marriage, sexual activity, fertility preferences, awareness and use of family planning methods, breastfeeding practices, nutritional status of women and young children, childhood mortality, maternal and child health, awareness and behaviour regarding HIV/AIDS and other sexually transmitted infections (STIs), and knowledge and attitudes toward tuberculosis.
OBJECTIVES AND ORGANIZATION OF THE SURVEY
The 2009 SDHS is a nationally representative sample survey designed to provide information on population and health issues in Samoa. The primary goal of the survey is to develop a single integrated set of demographic and health data pertaining to the population of Samoa.
The survey was an initiative of the MOH under its Health Sector Wide Approach program (SWAp). The MOH emphasized the importance of conducting a nationally representative survey such as the SDHS to provide a broad range of data to help assess the health and demographic status of the Samoan population and to assist with monitoring and evaluation of various health and population indicators. Furthermore, the SDHS survey should improve the quality and quantity of the health and population data available to the MOH by other sources.
The SDHS was conducted during August and September 2009 by the Samoa Bureau of Statistics (SBS). The SBS worked in close collaboration with the MOH for guidance in areas pertaining to health. ICF Macro provided technical support for the survey through the MEASURE DHS project. Funding for the survey was provided by the World Bank/International Development Association (IDA), the Australian Agency for International Development (AusAID), and the New Zealand Agency for International Development (NZAID). UNICEF and UNFPA also provided financial support for the report writing.
The survey collected national and regional level data on fertility and contraceptive use, maternal and child health, adult health, tuberculosis, and HIV/AIDS and other sexually transmitted diseases. The survey obtained detailed information on these issues from women of reproductive age and, on certain topics, from men as well.
The survey results are intended to provide the information needed to evaluate existing social programs and to design new strategies for improving the health of Samoans and health services for the people of Samoa. The SDHS also contributes to the growing international database on demographic and health-related variables.
SUMMARY OF FINDINGS
- Fertility Levels and Trends. The 2009 SDHS findings indicate that a Samoan woman who is at the beginning of her childbearing years will, on average, give birth to 4.6 children by the end of her reproductive period (if fertility levels remain constant at the levels observed in the three-year period preceding the 2009 SDHS).
- Antenatal Care. The survey shows that over nine in ten women (93 percent) who had a live birth in the five years preceding the survey received antenatal care from a health care provider (doctor, nurse, midwife, or nurse aide) during the pregnancy of the most recent birth.
- Childhood Mortality. The reported level of under-five mortality in the 2009 SDHS is 15 deaths per 1,000 births during the most recent five-year period before the survey. This implies that at least 1 in every 66 children born in Samoa during the period died before reaching a fifth birthday. The infant mortality rate recorded in the survey for the same period is 9 deaths per 1,000 live births.
- Breastfeeding Practices. The results indicate that 92 percent of children born in the past five years have been breastfed at some time. For last-born children who were breastfed, 88 percent started breastfeeding within one hour of birth and 97 percent started breastfeeding within the first 24 hours after delivery.
- Awareness of HIV/AIDS. Knowledge of HIV/AIDS is quite high in Samoa: 85 percent of women and 87 percent of men have heard of HIV/AIDS.
- Attitudes towards People Living with HIV/AIDS. It is encouraging to see that 65 percent of women and 77 percent of men would be willing to care in their home for a family member sick with AIDS.
Sample survey data
- Household
- Women age 15-49
- Men age 15-54
Scope
The Samoa Demographic and Health Survey 2009 covers the following topics:
- Background characteristics (education, residential history, media exposure, etc.)
- Birth history
- Antenatal, delivery, and postnatal care
- Knowledge, attitudes, and use of family planning methods
- Fertility preferences
- Marriage, woman's work, and husband's background characteristics
- Breastfeeding and infant feeding practices
- Vaccinations and childhood illnesses
- Childhood mortality
- Knowledge of and attitudes toward AIDS and other sexually transmitted diseases
- Knowledge of and attitudes toward tuberculosis
- Other health issues
Coverage
- National, Samoa as a whole
- Regional, Each of the four regions in Samoa: (1) Apia urban area, (2) North West Upolu, (3) Rest of Upolu, and (4) Savaii
- Urban and rural areas of Samoa (each as a separate domain)
The population covered in the 2009 SDHS is the universe of all women age 15-49 in Samoa. Every other household selected for the women's sample was also eligible for the men's sample (men age 15-54).
Producers and sponsors
| Name |
|---|
| Samoa Bureaus of Statistics (SBS) |
| Samoa Ministry of Health (MOH) |
| Name | Role |
|---|---|
| ICF Macro | Technical assistance |
| Name |
|---|
| World Bank/International Development Association |
| Australian Agency for International Development |
| New Zealand Agency for International Development |
| United Nations Children’s Fund |
| United Nations Population Fund |
Sampling
The 2009 SDHS survey is designed to allow reliable estimation of key demographic and health indicators such as fertility, contraceptive prevalence, and infant and child mortality.
The major domains distinguished in the tabulation of important characteristics for the eligible female population are:
- Samoa as a whole
- Each of the four regions in Samoa: (1) Apia urban area, (2) North West Upolu, (3) Rest of Upolu, and (4) Savaii
- Urban and rural areas of Samoa (each as a separate domain).
The population covered in the 2009 SDHS is the universe of all women age 15-49 in Samoa in a sample of 2,247 selected households. Every other household selected for the women's sample was also eligible for the men's sample (men age 15-54).
The primary sampling unit (PSU) for the 2009 SDHS was the cluster. As mentioned in Chapter 1, the 2009 SDHS sample was selected in two stages. The first stage involved selecting clusters from the master sample frame (the 2006 Population and Housing Census). In the second stage, all households in each selected cluster were listed. Households were then systematically selected from each cluster for participation in the survey. The design did not allow for replacement of clusters or households.
The sample was designed to include 10 percent of the households in rural areas and 12 percent of the households in urban areas. The sample was designed to permit detailed analysis of most indicators for the national level, for urban and rural areas separately, and for each of the four regions (Apia urban area, North West Upolu, the rest of Upolu, and Savaii). Overall, a total of 296 primary sampling units or clusters were selected, 104 in urban areas and 192 in rural areas. Because Samoan households do not move frequently, a fresh household listing was not deemed to be necessary. Instead, a listing from November 2006 was used. In the urban clusters, 5 households were selected per cluster, whereas in the rural clusters, 10 households were selected per cluster. The number of clusters in each of the 4 geographical regions was calculated by dividing the total allocated number of households by the sample take of 5 for Apia urban area (the number of households for urban EAs) and 10 for other regions (the number of households for rural EAs). In each region EAs were stratified by urban location first and then by rural location. Clusters were selected systematically, with probability proportional to size.
A total of 2,247 households were selected for the sample, of which 2,066 were found occupied at the time of the fieldwork. Of these, 1,947 households were successfully interviewed, yielding a household response rate of 94 percent.
In the households interviewed, a total of 3,033 eligible women were identified, of whom 2,657 were interviewed, yielding a response rate of 88 percent. Survey results indicate that 1,689 eligible men were identified in the sub-sample of households selected for the male survey and 1,307 were successfully interviewed, yielding a response rate of 77 percent.
The household and women's response rates are slightly lower in urban (92 percent and 86 percent, respectively) than in rural areas (95 percent and 88 percent, respectively), but for men, the response rate is higher in urban (81 percent) than in rural areas (76 percent).
The principal reason for non-response among eligible women and men was the failure to find them at home despite repeated visits to the households. The substantially lower response rates for men reflect the more frequent and longer absences of men from the home.
Survey instrument
Three questionnaires were used in the SDHS: a Household Questionnaire, a Women's Questionnaire, and a Men's Questionnaire. The household and individual questionnaires were based on model survey instruments developed in the MEASURE DHS program. The model questionnaires were adapted to meet the current needs of Samoa. Each household selected for the SDHS was eligible for interview with the Household Questionnaire.
a) The Household Questionnaire was used to list all usual members of and visitors to the selected households and to collect information on the socio-economic status of the household. The first part of the Household Questionnaire collected information on the basic demographic data for Samoan households, such as age, sex, educational attainment, and relationship of each household member or visitor to the head of the household. . It was also used to identify the women and men who were eligible for the individual interview (i.e., women age 15-49 and men age 15-54). In the second part of the Household Questionnaire, there were questions on housing characteristics (e.g., the flooring material, the source of water, and the type of toilet facilities), on ownership of a variety of consumer goods, on ownership of land and farm animals, and other questions relating to the socio-economic status of the household.
b) The Women's Questionnaire was used to collect information from all women age 15-49 years and covered the following topics:
- Background characteristics (education, residential history, media exposure, etc.)
- Birth history
- Antenatal, delivery, and postnatal care
- Knowledge, attitudes, and use of family planning methods
- Fertility preferences
- Marriage, woman's work, and husband's background characteristics
- Breastfeeding and infant feeding practices
- Vaccinations and childhood illnesses
- Childhood mortality
- Knowledge of and attitudes toward AIDS and other sexually transmitted diseases
- Knowledge of and attitudes toward tuberculosis
- Other health issues
c) The Men's Questionnaire, administered to all men age 15-54 years living in every other household, collected information similar to that on the Women's Questionnaire but was shorter because it did not contain questions on reproductive history, maternal and child health, and nutrition.
After finalization of the questionnaires in English, they were translated into Samoan.
Data collection
| Start | End |
|---|---|
| 2009-08 | 2009-09 |
| Name |
|---|
| Samoa Bureaus of Statistics |
PRETEST
All three survey questionnaires were pretested. The pretest training was also used as a tool for the training of trainers. The main objectives of the pretest were to provide experience for the trainers, who in turn trained the field staff during the main training, to test the survey instruments and logistics, and to build capacity of the survey team. An ICF Macro consultant visited Apia to conduct the pretest training and to assist with the pretest fieldwork.
Pretest training and fieldwork were conducted from 29 June to 10 July 2009 for 27 participants: 15 women and 12 men. Training entailed classroom discussions and practice focusing on the three survey questionnaires: the Household Questionnaire, the Women's Questionnaire, and the Men's Questionnaire. Guest speakers from the MOH were invited to make short presentations on family planning, child health, and nutrition programmes being implemented in Samoa. The participants actively discussed the questionnaires and made suggestions for modifications. Based on these suggestions, both English and Samoan versions of the questionnaires were updated for the pretest fieldwork. Participants were divided into 9 teams and participated in one day of field practice in one selected area that was not part of the survey sample. A total of 20 household interviews, 15 women's interviews, and 12 men's interviews were completed. Interviews were conducted in both English and Samoan. By the end of the pretest, a few errors in skip patterns and translation had been identified and corrected.
TRAINING
The main training of the survey field personnel was conducted for a period of 15 days from 20 July to 7 August 2009 in Apia. A total of 97 persons from various backgrounds were trained; 9 supervisors, 9 field editors, 54 female interviewers, 18 male interviewers, and 7 office editors.
The training of survey field staff consisted of a detailed, question-by-question explanation of the questionnaires, reading of the interviewer's manual, demonstrations, practice interviewing in small groups and pairs, and tests. Guest speakers were invited to give lectures about family planning and immunisation programmes in Samoa. Each section of the questionnaire was tested. The test results were used to reinforce understanding of key topics among the trainees and to strengthen their interviewing skills. Training included two days of field practice in communities in and around the training site that were not included in the 2009 SDHS sample. Additional training was held for field supervisors and editors.
FIELDWORK
Fieldwork for the main survey lasted from 10 August to 5 September 2009. Senior staff from SBS and MOH coordinated and supervised the fieldwork activities. Field staff were divided into 9 teams; 2 teams worked in the Apia Urban Area, 3 teams worked in North-West Upolu, 2 teams worked in the Rest of Upolu, and 2 teams worked in the Savaii region. Each team was composed of 1 supervisor, 1 field editor, 6 female interviewers, and 2 male interviewers. Each team was assigned a driver and a vehicle.
Data processing
The processing of the SDHS results began shortly after the fieldwork started. Data editing was first done in the field by field editors and supervisors. Completed and edited questionnaires for each cluster were packed and delivered to the SDHS Centre at Moto'otua where they were entered and edited by data processing personnel. The data processing team was composed of 15 data entry operators, 1 data entry supervisor with 2 assistants, and 7 office editors working in two shifts. Data operators and supervisors went through a one-week training program conducted with the technical assistance of ICF Macro. Data were entered using CSPro, a programme specially developed for use in household based surveys and censuses. All data were entered twice (100 percent verification). The concurrent processing of the data was an advantage because the survey technical staff were able to advise field teams of problems detected during the data entry using tables generated to check various data quality parameters. As a result, specific feedback was given to the teams to improve their performances. The data entry and editing phase of the survey was completed in February 2010.
Data appraisal
Sampling errors, on the other hand, can be evaluated statistically. The sample of respondents selected in the 2009 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 2009 SDHS sample is the result of a multi-stage stratified design, and, consequently, it was necessary to use more complex formulas. The computer software used to calculate sampling errors for the 2009 SDHS is a Macro SAS procedure. This procedure 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 formulas. Each replication considers all but one cluster in the calculation of the estimates. Pseudo-independent replications are thus created. In the 2009 JIDHS, there were 285 non-empty clusters. Hence, 930 replications were created.
In addition to the standard error, the design effect (DEFT) for each estimate is calculated, 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. The relative standard error and confidence limits for the estimates are also calculated.
Sampling errors for the 2009 SDHS 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 four geographical 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) 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). 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 childbearing.
The confidence interval (e.g., as calculated for children ever born to women age 40-49) can be interpreted as follows: the overall average from the national sample is 4.559 and its standard error is 0.116. Therefore, to obtain the 95 percent confidence limits, one adds and subtracts twice the standard error to the sample estimate, i.e., 4.559±2×0.116. 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 4.326 and 4.791.
For the total sample, the value of the DEFT, averaged over all variables, is 1.05. This means that, due to multi-stage clustering of the sample, the average standard error is increased by a factor of 1.05 over that in an equivalent simple random sample.
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 2009 Samoa DHS (SDHS) to minimize this type of error, non-sampling errors are impossible to avoid and difficult to evaluate statistically.
Data Access
| Name | Affiliation | URL | |
|---|---|---|---|
| MEASURE DHS | ICF International | www.measuredhs.com | archive@measuredhs.com |
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
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.
Contacts
| Name | URL | |
|---|---|---|
| General Inquiries | info@measuredhs.com | www.measuredhs.com |
| Data and Data Related Resources | archive@measuredhs.com | www.measuredhs.com |
Metadata production
DDI_WSM_2009_DHS_v01_M
| Name | Role |
|---|---|
| World Bank, Development Economics Data Group | Generation of DDI documentation |
2012-04-07