SAGE Cohorts: 2002-2009, Background and Objectives

The WHO Multi-Country Studies unit developed the Study on Global AGEing and Adult Health (SAGE) as part of a Longitudinal Survey Programme to compile comprehensive longitudinal information on the health and well-being of adult populations and the ageing process. The core SAGE collects data on respondents aged 18+ years, with an emphasis on populations aged 50+ years, from nationally representative samples in six countries (China, Ghana, India, Mexico, Russian Federation and South Africa). The survey instruments and methods described on this website were adapted from those used by the World Health Survey (WHS) and/or from 16 surveys on ageing (including the US Health and Retirement Survey (HRS) and the UK English Longitudinal Study of Ageing (ELSA)).

Household and individual level data on persons aged 50+ years are available from 23 countries, including links to other data collection efforts such as the Study on Health, Ageing and Retirement in Europe (SHARE) and demographic surveillance fieldsites in INDEPTH. A further set of countries in Latin America and Europe are lined up to join future rounds of SAGE. Survey tools for SAGE-INDEPTH and SAGE-SHARE are available through this website (click on link, "3. Additional SAGE Data and Methods"), with data available on request.

This study and survey programme is supported by the Behavioral and Social Research Program at the National Institute on Aging, National Institutes of Health, USA.

Primary 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
• 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 Wave 0: baseline cohort from WHS 2002-04

SAGE Wave 0: A baseline cohort was created during the 2002-2004 round of the World Health Survey (WHS) and contains data on the situation of 65,964 adults aged 18 years and older, including over 20,000 persons aged 50 years and older. Nationally representative sampling frames were used to identify adults aged 18+ for interview. Oversampling of older adults (aged 50+) was included in three countries. Questionnaires and data are available by clicking on "2. Core SAGE Survey Instruments and Data".

Samples of these respondents in Ghana were included in the SAGE pilot study and in five of the six participating countries as part of SAGE Wave 1. Manuscripts have been submitted to peer-reviewed journals and will be posted here when published.

SAGE pilot study (2005)

SAGE Pilot: The SAGE questionnaire was piloted in over 1500 respondents in three countries, Ghana, India and Tanzania in 2005. Included in the data set were 140 WHS follow-up respondents from Ghana and 76 retest interviews. Data collected included income, expenditures and transfers; work history; self-reported assessments of health linked to anchoring vignettes; risk factors; health care utilization; measured performance tests on a range of different domains of health; well-being, happiness and quality of life; and biomarkers. Questionnaires are available on this website (click on link to the right, "2. SAGE Survey Instruments").

SAGE Wave 1 (2007-09)

SAGE Wave 1: Implementation of the full SAGE was from 2007 to 2009 in six core countries over different regions of the world (China, Ghana, India, Mexico, Russian Federation and South Africa) with completion anticipated in the first half of 2009. The unique study design allowed for both follow-up and new respondents in Wave 1. 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. The target sample size was 5000 households with at least one person aged 50+ years and 1000 households with an 18 to 49 year old respondent. 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 (using the IQ Code).

In consultation with the Ministry of Health in China and China CDC, a new sampling design was used for SAGE in China drawn from an existing national surveillance system. In India, a representative sample of six states was included, taking into consideration population size and level of development, and can be modelled to a nationally representative sample. The Russian Federation's sample was extended to the east (as compared to the Wave 0 sample) to include respondents from the "Asian" region of the country. Questionnaires are available on this website (click on link to the right, "2. SAGE Survey Instruments").

The Governments of China, Mexico and South Africa provided additional financial support for implementing the survey in their respective countries.

SAGE Wave 2 (2010-11)

SAGE Wave 2: WHO secured funding through the U.S. National Institute on Aging, Behavioral and Social Research Program to implement SAGE Wave 2 in 2010-11 in these six countries. Survey instruments, methodological developments and data will be available through this website. After the Wave 2 round of data collection, pending financial support, future waves of SAGE to be implemented every two years.

SAGE on Wikipedia

Additional information about SAGE is available on Wikipedia at: WikiSAGE.

Core SAGE Survey Instruments and Data

SAGE Data Users Agreement

SAGE_UsersAgreement.pdf [pdf 181kb]

Download and complete the Users Agreement by clicking on the link above. Details about emailing the completed and signed document, requesting SAGE data, are listed below.

Country-specific adaptations to SAGE questionnaires

Country-specific adaptations for SAGE questionnaires and data are available on request.

WHS/SAGE Wave 0 (2002-04)

Survey instruments are available here . Data are in the public domain for Ghana, China, India, Mexico, Russian Federation, South Africa and 64 other countries participating in the WHS and are available through WHO at no cost. Wave 0 meta- and micro-data are available on request at no cost. Complete and send a Users Agreement (see top of page to download form) via email with the subject line, "WHS/SAGE Wave 0 - Users Agreement"). A password will be forwarded to legitimate researchers to access the data via the WHO World Health Survey results.

SAGE Pilot study (2005)

The survey instrument for SAGE was based on surveys created as part of the World Health Organization's World Health Survey programme , comparisons to 16 other cross-sectional or longitudinal studies on ageing (including the US Health and Retirement Survey and the English Longitudinal Study on Ageing), recommendations from an expert Advisory Group, and cognitive testing of a draft instrument in two countries (South Africa and Viet Nam in 2004). The resulting survey instrument was piloted in Ghana, India and Tanzania in April through July 2005. The individual questionnaire was implemented in five rotations to decrease respondent and interviewer burden - with the Sections 2000 and 7000 differing (see box).

The micro-data are in the public domain and available through WHO at no cost on request. Complete and send a Users Agreement (available at top of page) via email with subject line, "SAGE Pilot - Users Agreement"). A password will be forwarded to legitimate researchers to access the data.

Pilot - SAGE HHQ

Pilot - SAGE Individual Q

Questionnaire appendix, India pilot.

SAGE Wave 1 (2007-09)

A FIRST RELEASE of partially cleaned, unweighted micro-data, SAGE 1.0.0, are now in the public domain and available through WHO at no cost on request for Ghana, India, Russian Federation and South Africa. A first release for China and Mexico data will be ready in early 2010. Requests should include a completed Users Agreement form (see top of page to download form) and send via email. with subject line, "SAGE Wave 1 first release - Users Agreement"). A password and web link will be forwarded to legitimate researchers to access the data. Users are requested to use the following acknowledgement: “This paper uses data from WHO SAGE version 1.0.0. SAGE was supported by the US National Institute on Aging, Division of Behavioral and Social Research through an Inter-Agency Agreement.” SAGE version 1.1.0, cleaned and weighted, will be available after April 2010.

The SAGE survey instruments assessed health status and health systems from a household and individual perspective. SAGE also evaluated perceptions of well-being and more objective measures of health, including measured performance tests: 4m timed walk; spirometry; cognitive battery (verbal fluency, immediate and delayed recall, digit span forward and backward); near and distance vision; and, grip strength; and biomarkers: blood pressure and pulse rate; height and weight; hip and waist circumference; and, blood spot from fingerprick.

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. Survey materials can be downloaded by clicking on the links below.

Wave 1 Household Questionnaire .

• 0000 Coversheet
• 0100 Sampling Information
• 0200 Geocoding and GPS Information
• 0300 Recontact Information
• 0350 Contact Record
• 0400 Household Roster
• 0450 Kish Tables and Household Consent
• 0500 Housing
• 0600 Household and Family Support Networks and Transfers
• 0700 Assets and Household Income
• 0800 Household Expenditures
• 0900 Interviewer Observations
• 0900 Verbal Autopsy

Wave 1 Individual Questionnaire

• 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

Wave 1 Proxy Respondent Questionnaire

• 0 Proxy Consent Form
• 1 IQ Code
• 2 Health State Descriptions
• 4 Chronic Conditions and Health Services Coverage
• 5 Health Care Utilization

Verbal Autopsy Questionnaire

Wave 1 Survey Manual (QxQ Guide)

OTHER KEY ISSUES FOR SAGE

• Adapting the instruments to address local concerns / addressing methodological issues through focused studies, for example: caregiving burden in sub-Saharan Africa; nutritional assessment in older adults; culture-fair cognitive assessments;
• Addressing problems of accuracy in age-reporting;
• Planning effective follow-up strategies – taking into account migration and attrition issues;
• Improving cross-national comparability of data through additional validation studies of survey methodologies;
• Testing and validating new, novel methods – such as the Day Reconstruction Method as part of the Subjective well-being and quality of life module; and,
• Developing linkages with national and local data collection efforts (for example, HRS, ELSA, SHARE, INDEPTH, CHARLs, LASI, SABE, NFHS, ALSWH and others).

Additional SAGE Data and Methods

SAGE - INDEPTH

A short version of the SAGE questionnaire, focusing on health and well-being, has been implemented during routine surveillance rounds in nine demographic surveillance sites from the International Network for the continuous Demographic Evaluation of Populations and Their Health in developing countries (INDEPTH): South Africa (Agincourt and Hlabisa), Viet Nam (Filabavi), Tanzania (Ifakara), Bangladesh (Matlab), Kenya (Nairobi), Ghana (Navrongo), Indonesia (Purworejo), and India (Vadu). The full SAGE instrument was also implemented in the Agincourt, Navrongo and Vadu fieldsites in smaller random samples. Our goals are to develop common measurement strategies where possible and develop methods to link routine surveillance data and longitudinal survey data. Links to the summary Qs are available below. Data will be available in late 2009 at no cost to researchers through INDEPTH and WHO on request . A writing and dissemination workshop is planned at Harvard University in April 2010.

SAGE-INDEPTH summary Q generic Set A (Affect & Mobility) [pdf 296kb]
SAGE-INDEPTH summary Qs, Set B (Pain & Personal relationships) [pdf 297kb]
SAGE-INDEPTH summary Qs, Set C (Vision, Sleep & Energy) [pdf 267kb]
SAGE-INDEPTH summary Qs, Set D (Cognition & Self-care) [pdf 296kb]

SAGE and SHARE

The health state descriptions module and vignettes were added to the Study on Health, Ageing and Retirement in Europe (SHARE) data collection instrument in 2004 in eight countries. This module was again included in the first round of follow-up in 2007 in those same eight countries, plus in an additional three countries. Links to the vignette Qs are available from the SHARE/COMPARE website. Data from Wave 1 are available at no cost to researchers through SHARE and WHO on request . Wave 2 data are available through the SHARE website.

More SAGE in Europe

The WHO was part of a consortium, that secured support as part of the European Commission's Seventh Framework Programme (FP7) to implement SAGE-like health, disability, well-being and health system utilization studies in a number of European countries. COURAGE, based on SAGE, will be implemented in Finland, Poland and Spain in 2010.

WHS+ IN GCC COUNTRIES AND YEMEN

The Gulf Cooperation Council countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates) and Yemen are implementing the WHS+ in 2007-09. The survey instrument is a combination of the SAGE and WHS questions, modules and methods. WHO is providing technical and some financial support, with the GCC countries providing the majority of the financial support. Survey tools and data will be available for these countries through WHO HQ and WHO EMRO on request.

SAGE OFFERS UNIQUE OPPORTUNITIES FOR FURTHER METHODOLOGICAL DEVELOPMENTS

• Small area analyses – Given that sample sizes will be limited by costs, in order to develop robust estimates for parameters of interest, we will borrow from techniques developed for small area analysis for sub-population estimates by sociodemographic characteristics and geographic distribution (including sub-national estimates).
• Mortality rate estimation techniques and causes of death in this population need to be improved especially in the developing world. Given that samples sizes in surveys will be insufficient to provide robust estimates, linkages with other vital registration methods or sample registration surveys will be sought.
• Attrition in cohort studies with longitudinal follow-up will always be a concern. We will ensure that SAGE survey design and analytic techniques are informed by the current state of the art and offer an opportunity to develop new methods.
• Distribution of health and health related outcomes in this population, especially across sociodemographic gradients in developing countries, offers an opportunity to assess equity issues with novel techniques.
• Improvements in the measurement of self-related health states and morbidity will be made using measured performance tests and biomarker data. Techniques to adjust for biases in self-report will be developed.

Funding and Advisory Group

Funding agency and financial support

The National Institute on Aging, Behavioural and Social Research Program (NIA BSR) has provided the financial support for this project and has been instrumental in cross-national studies on ageing. NIA BSR has facilitated numerous forums for in-depth discussions about study content, design, methods, innovation, analysis, implementation and dissemination. We support the NIA position on public-access data sets and broad dissemination of results.

The governments of China, Mexico and South Africa contributed financial and/or in-kind support to the implementation of SAGE in their respective countries. Governments of all participating countries work with WHO on the implementation of SAGE.

Advisory Group

SAGE has been developed with input from an expert Advisory Group. Members include a dynamic group of experts in health, well-being, ageing, biomarkers, economics, retirement, demography, statistics, survey methods and other disciplines, combined with years of experience in longitudinal studies and study design. SAGE was created with local communities, local and national governments and the national/international research, policy and health/social systems planning communities as primary consumers of the resulting information.

:: SAGE Advisory Group general Terms of Reference [pdf 43kb]
:: SAGE Advisory Group (current and past contributors) [pdf 120kb]

Related Links and Data Archiving

:: The Minimum Data Set Project on Ageing and Adult Health in sub-Saharan Africa

:: The National Institute on Aging, Behavioral and Social Research Program (BSR)
Supports basic social and behavioural research and research training on the processes of aging at both the individual and societal level. BSR provides financial support and technical input for SAGE.

:: The INDEPTH network
An International Network of field sites with continuous Demographic Evaluation of Populations and Their Health in developing countries vision is to harness the collective potential of the world's community-based longitudinal demographic surveillance initiatives in resource constrained countries to provide a better, empirical understanding of health and social issues, and to apply this understanding to alleviate the most severe health and social challenges. A multi-site study platform for adult health is being developed with WHO and NIA.

:: Help Age International
A global advocacy organization committed to research and action for policy development.

:: US Census Bureau
Contributes to the development of high quality demographic and mortality data.

:: Study on Health and Retirement in Europe (SHARE)
Collects data about Europeans aged 50 and older in 11 countries in order to shed light on one of the most dramatic challenges in the years to come – population ageing. Select modules from SAGE have been included in the SHARE survey instrument.

:: RAND's MegaMetaData Repository
SAGE will be working with RAND to add all related meta-data to this multi-survey effort.

:: University of Michigan's NACDA archives
WHO will work with the University of Michigan's Inter-University Consortium for Political and Social Research (ICPSR) National Archive of Computerized Data on Aging (NACDA) to deposit SAGE data in its archives. The ICPSR provides technical and practical support for researchers and students wanting to use and analyze the data. We hope this will be one more avenue for researchers and analysts to access SAGE data.

:: Sociometrics Corporation, data archives
The Sociometrics Corporation will archive SAGE Wave 0, Pilot and Wave 1 data sets. WHO is currently working to deposit SAGE data into their Data Archive of Social Research on Aging (DASRA). Sociometrics provides data access support and training.