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
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
To provide a public-access information base to engage all stakeholders, including national policy makers and health systems planners, in planning and decision-making processes about the health and well-being of older adults
SAGE's first full round of data collection included both follow-up and new respondents in most participating countries. The goal of the sampling design was to obtain a nationally representative cohort of persons aged 50 years and older, with a smaller cohort of persons aged 18 to 49 for comparison purposes. In the older households, all persons aged 50+ years (for example, spouses and siblings) were invited to participate. Proxy respondents were identified for respondents who were unable to respond for themselves. Standardized SAGE survey instruments were used in all countries consisting of five main parts: 1) household questionnaire; 2) individual questionnaire; 3) proxy questionnaire; 4) verbal autopsy questionnaire; and, 5) appendices including showcards. A VAQ was completed for deaths in the household over the last 24 months. The procedures for including country-specific adaptations to the standardized questionnaire and translations into local languages from English follow those developed by and used for the World Health Survey.
0100 Sampling Information
0200 Geocoding and GPS Information
0300 Recontact Information
0350 Contact Record
0400 Household Roster
0450 Kish Tables and Household Consent
0600 Household and Family Support Networks and Transfers
0700 Assets and Household Income
0800 Household Expenditures
0900 Interviewer Observations
1000 Socio-Demographic Characteristics
1500 Work History and Benefits
2000 Health State Descriptions and Vignettes
2500 Anthropometrics, Performance Tests and Biomarkers
3000 Risk Factors and Preventive Health Behaviours
4000 Chronic Conditions and Health Services Coverage
5000 Health Care Utilization
6000 Social Cohesion
7000 Subjective Well-Being and Quality of Life (WHOQoL-8 and Day Reconstruction Method)
8000 Impact of Caregiving
9000 Interviewer Assessment
Kind of Data
Sample survey data [ssd]
Unit of Analysis
households and individuals
v01: Edited, anonymous dataset for public distribution.
Study on Global Ageing and Adult Health (SAGE)
Ageing, Alcohol, Asthma, Blindness, Cancer, Cataract, Cervical cancer, Chronic diseases, COPD, Depression, Diabetes, Diet, Disabilities, Epidemiology, Health financing, Health services, Health surveys, Health systems, Heart disease, Indoor air pollution, Injuries traffic, Mapping, Noncommunicable diseases, Nutrition, Obesity, Oral Health, Passive smoking, Physical activity, Poverty, Primary health care, Risk factors, Sanitation, Social determinants of health, Statistics, Stroke, Suicide, Tobacco, Visual impairment, Water, Women's health
WHO Health topics
Unit of Analysis
households and individuals
The household section of the survey covered all households in all ten administrative regions in Ghana. Institutionalised populations are excluded. 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.
Producers and sponsors
Authoring entity/Primary investigators
Professor R. Biritwum
Department of Community Health, Ghana Medical School
US National Institute on Aging
Financial support through Interagency Agreements (OGHA 04034785; YA1323-08-CN-0020; Y1-AG-1005-01) and Grants (R01-AG034479; IR21-AG034263-0182)
Dr Richard Suzman
The National Institute on Aging's Division of Behavioral and Social Research
Dr Suzman was Instrumental in providing continuous intellectual and other technical support to SAGE and has made the entire endeavour possible.
Ghana used a stratified, multistage cluster design.
The sample was stratified by administrative region (Ashanti, Brong Ahafo, Central, Eastern, Greater Accra, Northern, Upper East, Upper West, Volta and Western) and type of locality (urban/rural) resulting in 20 strata and is nationally representative.
The Census Enumerated Areas (CEA) of the 2000 Population and Housing Census was used as the sampling frame.
A sample of 251 EAs was selected as the primary sampling units (PSU). One of the selected PSUs was not used. This was because the EA which was expected to be located at Korle Bu Teaching hospital cccould not be traced. 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 census frame). EAs were then selected from each stratum 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, a listing of the households was conducted to classify each household into the following mutually exclusive categories:
(1) WHS/SAGE Wave 0 follow-up households with one or more members aged 50 years or more;
(2) New households with one or more members aged 50 years or more;
(3) WHS/SAGE Wave 0 follow-up households which did not include any members aged 50 years or more, but included residents aged 18-49; and,
(4) New households which did not include any members aged 50 years or more, but included residents aged 18-49.
Twenty-four households were randomly selected from each selected EA. All WHS/SAGE Wave 0 follow-up 50-plus households were eligible for the household interview (one household respondent was selected). Twenty such households were selected. If this target number was not reached, then the balance was selected using systematic sampling from the new 50-plus households. All 50+ members of the household were eligible for the individual interview (multiple individual interviews possible in these households).
Household weights(variable hhweight) for analysis at household level and individual weights(variable pweight) for analysis at person level were calculated.
These were based on the selection probability at each stage of selection. Household weights were post-stratified by region and locality according to the 2010 household projections.
Individual weights were post-stratified by region, locality, sex and age-groups(18-49, 50-59, 60-69, 70+) according to the 2009 Projected population estimates provided by Stats Ghana.
Weights are not normalised.
Dates of Data Collection (YYYY/MM/DD)
Mode of data collection
Face-to-face [f2f] PAPI
Type of Research Instrument
The questionnaires were based on the WHS Model Questionnaire with some modification and many new additions. A household questionnaire was administered to all households eligible for the study. A Verbal Autopsy questionnaire was administered to households that had a death in the last 24 months. An Individual questionniare was administered to eligible respondents identified from the household roster. A Proxy questionnaire was administered to individual respondents who had cognitive limitations. The questionnaires were developed in English and were piloted as part of the SAGE pretest in 2005. All documents were translated into three local languanges: Akan, Ga and Twi. All SAGE generic questionnaires are available as external resources.
Department of Community Health, Ghana Medical School
University of Ghana
Data editing took place at a number of stages including:
(1) office editing and coding
(2) during data entry
(3) structural checking of the CSPro files
(4) range and consistency secondary edits in Stata
Nirmala Naidoo, Health Statistics and Information Systems
World Health Organization
The user undertakes:
(1) to keep confidential any information concerning individual persons or households.
(2) not to distribute the data to any other user.
(3) to use the data for scientific research only.
(4) to share any planned publications with WHO prior to publication.
Publications based on SAGE data should use the following acknowledgement: "This paper uses data from the WHO Study on Global AGEing and Adult Health (SAGE)."
Disclaimer and copyrights
The data is being distributed without warranty of any kind. The responsibility for the use of the data lies with the user. In no event shall the World Health Organization be liable for damages arising from its use.