The Study on Global Ageing and Adult Health is the second round of the World Health Survey which was conducted in 2003. SAGE surveys are designed by the World Health Organization and implemented by national agencies in participating countries.
The multi-country Study on Global Ageing and Adult Health (SAGE) is run by the World Health Organization's Multi-Country Studies unit in the Innovation, Information, Evidence and Research Cluster. SAGE is part of the unit's Longitudinal Study Programme which is compiling longitudinal data on the health and well-being of adult populations, and the ageing process, through primary data collection and secondary data analysis. SAGE baseline data (Wave 0, 2002/3) was collected as part of WHO's World Health Survey http://www.who.int/healthinfo/survey/en/index.html (WHS). SAGE Wave 1 (2007/10) 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.
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
v01: Edited, anonymous dataset for public distribution.
The scope of the Study on Global Ageing and Adult Health includes:
HOUSEHOLD: household characteristics, housing, household and family support, assets and household income, household expenditure.
INDIVIDUAL: socio demographic characteristics, work history, health state, anthropometrics, performance tests and biomarkers, risk factors, chronic conditions and health service coverage, health care utilisation, social cohesion, subjective well-being and quality of life, caregiving.
The household section of the survey covered all households in all 32 federal states in Mexico. 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
Instituto Nacional de Salud Pública
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
In Mexico strata were defined by locality (metropolitan, urban, rural).
A sub-sample of 211 PSUs were selected from the 797 WHS PSUs.
The Basic Geo-Statistical Areas (AGEB) defined by the National Institute of Statistics (INEGI) constitutes a PSU.
PSUs were selected probability proportional to three factors:
a) (WHS/SAGE Wave 0 50plus): number of WHS/SAGE Wave 0 50-plus interviewed at the PSU,
b) (State Population): population of the state to which the PSU belongs,
c) (WHS/SAGE Wave 0 PSU at county): number of PSUs selected from the county to which the PSU belongs for the WHS/SAGE Wave 0;
The first and third factors were included to reduce geographic dispersion. Factor two affords states with larger populations a greater chance of selection.
All WHS/SAGE Wave 0 individuals aged 50 years or older in the selected rural or urban PSUs and a random sample 90% of individuals aged 50 years or older in metropolitan PSUs who had been interviewed for the WHS/SAGE Wave 0 were included in the SAGE Wave 1 ''primary'' sample. The remaining 10% of WHS/SAGE Wave 0 individuals aged 50 years or older in metropolitan areas were then allocated as a ''replacement'' sample for individuals who could not be contacted or did not consent to participate in SAGE Wave 1. A systematic sample of 1000 WHS/SAGE Wave 0 individuals aged 18-49 across all selected PSUs was selected as the ''primary'' sample and 500 as a ''replacement'' sample.
This selection process resulted in a sample which had an over-representation of individuals from metropolitan strata; therefore, it was decided to increase the number of individuals aged 50 years or older from rural and urban strata. This was achieved by including individuals who had not been part of WHS/SAGE Wave 0 (which became a ''supplementary'' sample), although the household in which they lived included an individual from WHS/SAGE Wave 0. All individuals aged 50 or over were included from rural and urban ''18-49 households'' (that is, where an individual aged 18-49 was included in WHS/SAGE Wave 0) as part of the ''primary supplementary'' sample. A systematic random sample of individuals aged 50 years or older was then obtained from urban and rural households where an individual had already been selected as part of the 50 years and older or 18-49 samples. These individuals then formed part of the ''primary supplementary'' sample and the remainder (that is, those not systematically selected) were allocated to the ''replacement supplementary'' sample. Thus, all individuals aged 50 years or older who lived in households in urban and rural PSUs obtained for SAGE Wave 1 were selected as either a primary or replacement participant. A final ''replacement'' sample for the 50 and over age group was obtained from a systematic sample of all individuals aged 50 or over from households which included the individuals already selected for either the 50 and over or 18-49. This sampling strategy also provided participants who had not been included in WHS/SAGE Wave 0, but lived in a household where an individual had been part of WHS/SAGE Wave 0 (that is, the ''supplementary'' sample), in addition to follow-up of individuals who had been included in the WHS/SAGE Wave 0 sample.
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 locality according to the 2009 population census projections.
Individual weights were post-stratified by sex and age-groups (18-34, 35-49, 50-59, 60-105) according to the 2009 population census projections.
Weights are divided by 1000 and are not normalized.
Dates of Data Collection
Data Collection Mode
Face-to-face [f2f], CAPI
Instituto Nacional de Salud Pública
Ministry of Health
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 Spanish. All SAGE generic questionnaires are available as external resources.
Data editing took place at a number of stages including:
(1) office editing and coding
(2) during data entry
(3) structural checking of the FoxPro files
(4) range and consistency secondary edits in Stata
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.
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
Instituto Nacional de Salud Pública. Mexico Study on Global Ageing and Adult Health 2009-2010. Ref. MEX_2009_SAGE_v01_M. Dataset downloaded from www.measuredhs.com on [date]
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.