Description:
The data sets included in the SAGE 2007-08 study comprised household survey data, household members survey data and individual survey data.
396 of 600 targeted EAs (66%) were realised.
WHO ID Number: ZAF-WHO-SAGE-2007-v01
Abstract:
SAGE Wave 1 (2007/08) provides a comprehensive data set on the health and well-being of adults in six low and middle-income countries: China, Ghana, India, Mexico, Russian Federation and South Africa.
Objectives:
To obtain reliable, valid and comparable health, health-related and well-being data over a range of key domains for adult and older adult populations in nationally representative samples
To examine patterns and dynamics of age-related changes in health and well-being using longitudinal follow-up of a cohort as they age, and to investigate socio-economic consequences of these health changes
To supplement and cross-validate self-reported measures of health and the anchoring vignette approach to improving comparability of self-reported measures, through measured performance tests for selected health domains
To collect health examination and biomarker data that improves reliability of morbidity and risk factor data and to objectively monitor the effect of interventions
Additional Objectives:
To generate large cohorts of older adult populations and comparison cohorts of younger populations for following-up intermediate outcomes, monitoring trends, examining transitions and life events, and addressing relationships between determinants and health, well-being and health-related outcomes
To develop a mechanism to link survey data to demographic surveillance site data
To build linkages with other national and multi-country ageing studies
To improve the methodologies to enhance the reliability and validity of health outcomes and determinants data.
The data and documentation can be downloaded from the WHO website: http://www.who.int/healthinfo/sage/en/
Clinical measurements
Face-to-face interview
Physical measurements
The household section of the survey covered all households in all nine provinces in South Africa. The individual section covered all persons aged 18 years and older residing within individual households. As the focus of SAGE is older adults, a much larger sample of respondents aged 50 years and older were selected with a smaller comparative sample of respondents aged 18-49 years.
South Africa used a stratified multistage cluster sample design. Strata were defined by the nine provinces:
(Eastern Cape, Free State, Gauteng, Kwa-Zulu Natal, Limpopo, Mpumalanga, North West, Northern Cape and Western Cape),
locality (urban or rural),
and predominant race group (African/Black, White, Coloured and Indian/Asian).
As not all combinations of stratification variables were possible, there were 50 strata in total. The Human Sciences Research Council's master sample was used as the sampling frame which comprised 1000EAs. A sample of 600 EAs was selected as the primary sampling units(PSU).
The number of EAs to be selected from each strata was based on proportional allocation (determined by the number of EAs in each strata specified on the Master Sample). EAs were then selected from each strata with probability proportional to size; the measure of size being the number of individuals aged 50 years or more in the EA. In each selected EA 30 households were randomly selected from the Master Sample. A listing of the 30 selected households was conducted to classify each household into one of two mutually exclusive categories:
households with one or more members aged 50 years or more (defined as '50 plus households');
households which did not include any members aged 50 years or more, but included residents aged 18-49 (defined as '18-49 households').
All 50 plus households were eligible for the household interview, and all 50 plus members of the household were eligible for the individual interview. Two of the remaining 18-49 households were randomly selected for the household interview. In each of these household one person aged 18-49 was eligible for the individual interview, and the individual to be included was selected using a Kish Grid.
Stages of selection:
Strata: Province, Predominant Race Group, Locality=50
PSU: EAs=408 surveyed
SSU: Households=4020 surveyed
TSU: Individual=4227 surveyed