Study on Global Ageing and Adult Health

The Study on Global Ageing and Adult Health (SAGE) is run by the World Health Organization's Statistics, Measurement and Analysis unit. An objective for SAGE is to compile comprehensive longitudinal data on the health and well-being of adult populations and the ageing process across different countries, through primary data collection and secondary data analysis.

SAGE baseline data (Wave 0, 2002–04) was collected as part of WHO's World Health Survey (WHS). A second round of data collection (Wave 1, 2007–10) is completed, expanding the sample sizes in each participating country (China, Ghana, India, Mexico, the Russian Federation and South Africa). Wave 2 (2015) data collection will be completed in 2015 in all six countries. Wave 2 is planned for 2016.

SAGE Wave 0 (2002/04)

A baseline cohort for the six participating countries was created as part of the larger World Health Survey effort 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. Samples of these respondents were followed-up as a part of SAGE Wave 1 (2007–10) data collection in four of the six SAGE countries (Ghana, India, Mexico and the Russian Federation). Meta- and micro-data are in the public domain through WHO at http://apps.who.int/healthinfo/systems/surveydata/index.php/catalog/whs.

Countries collaborating with SAGE

SAGE Wave 1 (2007/10)

Weighted data for China, Ghana, India, Mexico, Russian Federation and South Africa are in the public domain (see Study on global AGEing and Adult Health). SAGE's first full round of data collection included both follow-up and new respondents in four 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. 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. The pooled data set will include over 43,000 respondents (see table below).

Modules in SAGE W1 Questionnaires

Household Questionnaire

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 Verbal Autopsy

Individual Questionnaire

1000 Socio-Demographic Characteristics
1500 Work History and Benefits
2000 Health State Descriptions and Vignettes
2500 Anthropometrics, Performance Tests and Biomarkers
- Including: blood pressure, pulse rate, hip & waist circumferences, height, weight, grip strength, timed walk, vision, lung function, cognition, finger prick blood sample
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 & the Day Reconstruction Method) See also: Happiness
8000 Impact of Caregiving
9000 Interviewer Assessment

Proxy Questionnaire

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

Data collected, Wave 1

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 question by question guide (Survey Manual) is available. 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.

Country	World Bank economic category (2007)	Sample Size
China	Lower-Middle	14785
Ghana	Low	5573
India	Low	12198
Mexico	Upper-Middle	2734
Russian Federation	Upper-Middle	4947
South Africa	Upper-Middle	4227

Descriptive results from SAGE Wave 1 are available through a US Census Bureau/WHO report Shades of Gray: A Cross-Country Study of Health and Well-Being of the Older Populations in SAGE Countries, 2007-2010.

Background information on SAGE is also available through:
Kowal P, Chatterji S, Naidoo N, Biritwum R, Wu Fan, Lopez Ridaura R, Maximova T, Arokiasamy P, Phaswana-Mafuya N, Peltzer K, Williams S, Snodgrass JJ, Minicuci N, D'Este C, Boerma JT and the SAGE Collaborators. Data Resource Profile: The WHO Study on global AGEing and adult health (SAGE). Int J Epidemiol. 2012;41(6):1639-49.

SAGE Wave 2 (2015)

Data collection for SAGE Wave 2 started in late 2014 and will be completed in 2015 in all six SAGE countries.

Links to other studies

SAGE adapted methods and instruments used by the 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) to collect household data on persons aged 50 years and older in over 20 countries, as well as fostering links to other data collection efforts such as the Study on Health, Ageing and Retirement in Europe (SHARE), the Chinese Health and Retirement Survey (CHARLs), the Longitudinal Ageing Study in India (LASI).

SAGE-like surveys have been conducted as the World Health Survey Plus (WHS+) in the Gulf Cooperation Council countries (plus Yemen), as a short version of SAGE in eight demographic surveillance fieldsites INDEPTH; as a full SAGE in three INDEPTH fieldsites; and, as COURAGE in Europe in three European countries.

SAGE-INDEPTH

Data for the summary SAGE module added to INDEPTH census rounds in 2007 and 2008 is available through WHO SAGE and INDEPTH. These data include the SAGE health state descriptions, WHO Disability Assessment Schedule version 2 (WHODAS-II) and the WHO Quality of Life (WHOQoL) 8-item version as measures of health and subjective well-being, linked to selected sociodemographic data from the demographic surveillance fieldsites in eight countries (Bangladesh, Ghana, India, Indonesia, Kenya, South Africa, Tanzania and Viet Nam). The sample size is over 46,000 respondents. First results are published as 'Growing Older in Africa and Asia: Multicentre study on ageing, health and well-being' in the peer-reviewed open-access journal, Global Health Action.

Country (DSS Fieldsite)	World Bank economic category	Sample Size
Bangladesh (Matlab)	Low	4037
Ghana (Navrongo)	Lower-Middle	4584
India (Vadu)	Lower-Middle	5430
Indonesia (Purworejo)	Lower-Middle	12395
Kenya (Nairobi)	Low	2072
South Africa (Agincourt)	Upper-Middle	4085
Tanzania (Ifakara)	Low	5131
Viet Nam (Filabavi)	Lower-Middle	8535

SAGE-WOPS (HIV study)

Two waves of the SAGE Well-being of Older People Study (WOPS) HIV study has been conducted in two countries, South Africa and Uganda, with the goal of providing data on the effects of HIV/AIDS among older people infected or affected by HIV. The aim of this study was to describe the health status, well being and functional status among older people either infected with HIV themselves, or affected by HIV/AIDS in their families. The impacts of caregiving and ART were also examined. Wave 1 was completed in 2010/11 and Wave 2 was completed in 2013. Wave 3 is planned for 2015, and Wave 4 in 2017. Two initial papers from Wave 1 results are below.

Scholten F, Mugisha J, Seeley J, Kinyanda E, Nakubukwa S, Kowal P, Naidoo N, Boerma T, Chatterji S, Grosskurth H. Health and functional status among older people with HIV/AIDS in Uganda. BMC Pub Health. 2011;11:886.

Nyirenda M, Chatterji S, Falkingham J, Mutevedzi P, Hosegood V, Evandrou M, Kowal P, Newell M-L. An investigation of factors associated with the health and wellbeing of HIV-infected and HIV-affected older people in rural South Africa. BMC Pub Health. 2012;12:259.

Direction

The WHO's Statistics, Measurement and Analysis unit runs SAGE and is headed by Dr Somnath Chatterji. The unit is under the direction of Dr Ties Boerma in the Department of Health Statistics and Information Systems. Dr Chatterji is SAGE Principal Investigator, Dr Paul Kowal is co-Principal Investigator, Ms Nirmala Naidoo is the lead statistician, with regular contributions from other members of the WHO SMA unit. Survey teams in each participating country lead the data capture efforts, from data collection to dissemination, and contribute to analysis and manuscript preparation.

Wave 1 country Primary Investigators: Dr Wu Fan, Shanghai CDC, China; Prof Richard Biritwum, University of Ghana, Ghana; Prof Perianayagam Arokiasamy, IIPS, India; Ms Rosalba Roja, Dr Ruy Lopez Ridaura, Dr Mara Tellez Rojo, INSP, Mexico; Dr Tamara Maximova, RAMS, Russian Federation; and, Dr Refilwe Nancy Phaswana-Mafuya and Dr Karl Peltzer, HSRC, South Africa.
Wave 2 country Primary Investigators: Dr Wu Fan, Shanghai CDC, China; Prof Richard Biritwum and Dr Alfred Yawson, University of Ghana, Ghana; Prof Perianayagam Arokiasamy, IIPS, India; Mr Aaron Salinas Rodriguez and Ms Betty Soledad Manrique Espinoza, INSP, Mexico; Dr Tamara Maximova and Dr Vitaly Belov, RAMS, Russian Federation; and, Dr Stephen Rule, Outsourced Insight, South Africa.

Funding

SAGE and SAGE sub-studies are supported by the World Health Organization and the Division of Behavioral and Social Research at the National Institute on Aging (NIA BSR), US National Institutes of Health, through Interagency Agreements (OGHA 04034785; YA1323-08-CN-0020; Y1-AG-1005-01) with WHO and a Research Project Grant R01 AG034479. NIA BSR has facilitated forums for in-depth discussions about study content, design and implementation. The NIA BSR has been instrumental in promoting linkages between longitudinal studies on ageing and adult health around the world.

Governments in three countries, China, Mexico and South Africa, provided financial support for SAGE Wave 1. The University of Ghana provided financial and in-kind support. USAID funding contributed to an oversample of adult women in SAGE India Wave 1.

The European Commission under Seventh Framework Programme has provided financial support to implement a SAGE-like health status, quality of life and well-being study in Europe under the name "collaborative research on ageing in Europe (COURAGE in Europe)". Finland, Poland and Spain implemented the survey in 2010.