Population Ageing (2013) 6:5–27DOI 10.1007/s12062-013-9082-3A Review of Longitudinal Datasets on AgeingAngelika KaiserReceived: 18 December 2012 / Accepted: 3 February 2013 / Published online: 15 June 2013# Springer Science Business Media Dordrecht 2013Abstract The growth in longitudinal datasets on ageing have resulted from a recentglobal initiative, in a large part encouraged and partially funded by the NIA, over thepast 20 years in numerous countries eager to understand the complexities of theirageing societies. In the main these studies aim to collect data on population ageing interms of social, medical and environmental factors. Accordingly the studies beingcompared in this review focus primarily on health, wellbeing and social issues. Thesestudies have made it possible to measure, evaluate and understand a wide variety ofdeterminants of population change and helped to identify the challenges faced onmany levels for the twenty first century and beyond. They have enabled organisations, health care service providers and government more readily able to anticipateand be responsive to the need of the dynamics of the population change as not onlythe population rapidly increases but faces a significant rise in the percentage ofelderly persons. This review looks at the aim of each study, comparisons in methodology, key policy themes, benefits, collaborations with other datasets, gaps andchallenges and key findings to date. For further information, an appendix is attachedwith the contact details of the Principal investigator and study website.Keywords Longitudinal surveys . Datasets . Population ageingLongitudinal Datasets Contribution to Population Ageing1This review which has compared fifteen current studies and two under development,revealed a wide variety of types of national studies (Table 1).There are seven kinds of longitudinal data reviewed here. These include:&1personal interviews, self-enumerated questionnaires and clinical and home-basedinstruments (ALSA, TILDA);The information in this article is based on an outline which was sent to each study with specific questions.A. Kaiser (*)Oxford Institute of Population Ageing, University of Oxford, Oxford, UKe-mail: [email protected]

LASIMHASPSAESHAREMexican Health and Aging StudySwedish Panel Survey of Ageing and theElderlySurvey of Health, Ageing and Retirement inEuropeKloSAKorean Longitudinal Study of AgeingLongitudinal Aging Study in IndiaILSAJSTARHRSHealth and Retirement StudyJapanese Study of Aging and RetirementHILDAHousehold, Income and Labour Dynamics inAustraliaThe Italian Longitudinal Study on AgeingELSAGLASCLSACanadian Longitudinal Study on AgingGlobal Ageing SurveyCHARLSChina Health and Retirement LongitudinalStudyEnglish Longitudinal Study of AgeingALSAAcronymAustralian Longitudinal Study of AgeingEstablishedDatasetTable 1 Data sets reviewedHealth, socio-economic status, social andfamily networks in depth in 20 EuropeancountriesOlder persons’ living conditions, retirement,social inclusion, family relationships, healthdevelopmentHealth and socio-economicsAdult health, population ageing processesWork, income and health, disability and familytransfersEconomic, social, and health aspectsHealth and disease, physical & mental functionChanges in labour force participation andhealth transitionsHousehold, income and labour dynamicsHealth & retirement, attitudes, behaviours andexpectationsEconomic, social, psychological and healthChanging biological, medical, psychological,social, lifestyle and economic aspectsElderly households, elderly respondents andtheir spousesSocial, biomedical & environmental factorsPrimary purpose of Over 25,391 (Wave 1 only)110,00012,000 over 12 years50,00017,0002087 (Wave 1 followed byvarying responses)Number of 052002200820061992Launched50 years and over55 to 64 years50 years and over45 years and over45 years and over50 to 75 years65 to 84 years50 years and over15 years in privatehouseholds40 to 80 years50 years45 to 85 years45 years and over70 years and overAge range included6A. Kaiser

TILDAIrish Longitudinal Study on AgeingELSI-BrasilTHSLSBrazilian Longitudinal Study of AgeingScottish Longitudinal Study of AgeingUnder developmentAcronymDatasetTable 1 (continued)Health, population ageing in particular uniqueissues to ScotlandRelationships between health and functioning,economic position, social participation/networksand well-being; impact of environment &genetic factorsHealth, social and economic circumstancesPrimary purpose of study10,00015,00010 years10,000Number of participantsTBD20132009Launched45 years and over50 years and over50 years and overAge range includedA Review of Longitudinal Datasets on Ageing7

8A. Kaiser&household panel surveys which regularly follow-up some or all household members (over a specified age) and include components such as demographic background; family; health status and functioning; social networks and supports;social, civil and cultural participation; health care and insurance; work, retirementand pension; income, expenditure and assets (CHARLS, ELSA, GLAS, KLoSA,MHA & SHARE);cross-sectional surveys in which respondents were selected randomly (GLAS);longitudinal studies of individuals which begin in adolescence or adulthood;(ALSA) andenhanced in-person interviews that collect wide range of measures of physicalfunction, biomarker and DNA samples and (HRS, ILSA, LASI)computer-assisted personal interviewing (CAPI) studies which also link data fromother national studies (JSTAR, LASI & TILDA).&&&&Aim of Each Study and BackgroundThe studies being reviewed encompass an extensive range of elements includingexploration of the impact of social, biomedical and environmental factors on healthand well-being; a review of the demographic profile of households of the elderly; lifeand economic aspects; cultural influences in ageing; perception and the dynamicsbetween families and communities; and patterns in spending, retirement and socialwelfare. Most importantly, one common objective is the desire to provide governmentwith the tools it needs to develop policies and plans for its’ ageing society. The aimsof each study can be summarised as follows:The Australian Longitudinal Study of Ageing (ALSA) was launched in 1992as Australia’s first multi-dimensional population based study of human ageing.The general purpose was gain further understanding of how social, biomedicaland environmental factors are associated with age related changes in health andwell-being of persons aged 70 years and over. Emphasis was given in the overallstudy to defining and exploring the concept of healthy and successful ageing,particularly in a South Australian context.The China Health and Retirement Longitudinal Study (CHARLS) waslaunched in 2007 with the aim to set up a high quality, nationally representativeand publicly available micro-database that provides a wide range of informationabout the households of the elderly and also individual information on the elderlyrespondents and their spouses. CHARLS is a multidisciplinary research projectjointly carried out by China CDC and Peking university, with special attention tothe national aging population, a series of problems in health, economic and socialsecurity and etc. and worthy of long-term tracking.The Canadian Longitudinal Study on Aging (CLSA) a large, national, longterm study launched in 2010 will be collecting information on the changingbiological, medical, psychological, social, lifestyle and economic aspects ofpeople’s lives. These factors will be studied in order to understand how,individually and in combination, they have an impact in both maintaininghealth and in the development of disease and disability as people age. The

A Review of Longitudinal Datasets on Ageing9CLSA will be one of the most comprehensive studies of its kind undertaken to date, not only in Canada but around the world.The English Longitudinal Study of Ageing (ELSA) was the first study in theUK to connect the full range of topics necessary to understand the economic,social, psychological and health elements of the ageing process. (Chicago Coreon Biomarkers in Population-based Aging Research. ‘HRS-harmonized studiesall over the World’ Chicago Core on Biomarkers in Population Based AgingResearch 2005). One of ELSA’s key aims is to help the government plan for anageing population and longer periods of retirement and to ensure that the UK’shealthcare and pension systems will meet everyone’s needs.The Global Ageing Survey (GLAS) a study undertaken between 2005–2008(GLAS) by the Oxford Institute of Population Ageing in collaboration withHSBC Insurance included 25 countries in Asia, Americas, Europe and Africaand comprised cross comparative modules with HRS and SHARE on health andretirement, explored attitudes, expectations and behaviours towards later life andretirement, including financial planning for retirement.The University of Michigan Health and Retirement Study (HRS) is a longitudinalpanel study that explores the changes in labour force participation and the healthtransitions that individuals undergo toward the end of their working lives and in theyears that follow. Through expanding its science into new areas of biology andpsychology, it has become the most comprehensive study for understanding the livesof ageing Americans. Since its launch in 1992, the study has collected informationabout income, work, assets, pension plans, health insurance, disability, physicalhealth and functioning, cognitive functioning, and health care expenditures.The Household, Income and Labour Dynamics in Australia (HILDA) Survey,a household-based panel study collected its first wave of data in 2001 focusingon household composition, employment, income and wealth, and health andwell-being. Funded by the Australian Government, it is intended to be a majorresource for researchers and policy-makers about economic and subjective wellbeing, labour market dynamics and family dynamics.The Italian Longitudinal Study on Ageing (ILSA) launched in 1992 aimed tostudy the prevalence and incidence rates of common chronic conditions in the olderpopulation, and the identification of their risk and protective factors. ILSA was alsodesigned to assess age-associated physical and mental functional changes.The Japanese Study of Aging and Retirement (JSTAR) aimed to capture thediversity of the elderly population given the fact that the Japanese population isageing ahead of other developed countries and the government needed valuableinput for real-world policymaking. As a result, The Research Institute of Economy, Trade and Industry (RIETI) and Hitotsubashi University jointly launched acomprehensive survey of elderly people in 2007 to collect panel data on their lifeand health. This rich dataset provides information on how middle-aged andelderly Japanese live in terms of economic, social, and health outcomes, andhow these interact with their family status. The JSTAR project aims to providelongitudinal data enabling detailed policy-relevant comparisons to other industrialized countries (e.g. the Survey on Health, Aging and Retirement in Europe,the US Health and Retirement Study, the English Longitudinal Study on Aging,and similar surveys now launched in Korea, China, and India).

10A. KaiserThe Korean Longitudinal Study of Ageing (KLoSA) was first conducted in2006, to create the basic data needed to devise and implement effective social,economic policies to address the trends that emerge in the process of populationageing. Its aim was to collect information on work and income and health anddisability and includes detailed questions on family transfers. This statistical datacovers the following areas: Institutional reform and policy-making in preparationagainst the aged society require systematic build-up of data that can trackindividuals’ labour participation, income and asset status, spending patterns,retirement decisions, impact of social welfare, health, and intra-family transferof income, among others.The Longitudinal Aging Study in India (LASI) is being conducted as apartnership between the Harvard School of Public Health (HSPH), theInternational Institute for Population Sciences (IIPS), and the RAND Corporation. The study examines the physical, financial, and social correlates andimplications of population aging in India, with the aim of informing policiesthat could mitigate related challenges. It will allow a better understanding ofIndia’s adult health problems and population ageing. As one of the mostrecent established studies in 2009, LASI is fully collaborative with severalother key studies. The study is supported by a grant from the NationalInstitute of Aging, as well as by supplemental support from HSPH, IIPS, andRAND.The Mexican Health and Aging Study (MHAS) is a prospective panel study ofhealth and ageing in Mexico. The study is a collaborative effort among researchers from the Universities of Pennsylvania, Maryland, and Wisconsin inthe U.S., and the Instituto Nacional de Estadística, Geografia e Informática(INEGI) in Mexico. The overall goal of the study was to examine the ageingprocess and its disease and disability burden in a large representative panel ofolder Mexicans from a wide socio-economic spectrum.The Panel Survey of Ageing and the Elderly (PSAE) was conducted between2002 and 2003 to answer several key questions posed by the Government inSweden in conjunction with a directed focus by the country’s research councilson elderly people’s living conditions. The first question was to look at the farreaching social and economic consequences of the demographic challenge as thepopulation ages. The second was to look at ways to deal with: a) the extent towhich health status among the elderly improve, worsen or remain constant, b) theextent to which older people will remain in employment, c) the older socialnetworking and what type of support these networks will contribute and, d) andthe extent to which older people are productive even after they have left thelabour market. Through its unique design, integration with the annual Survey ofLiving Conditions (ULF) and the use of registry data, PSAE outset offersinformation with unique breadth and a longitudinal approach that offers theopportunity to study different stages of ageing of employment among olderworkers, from work to retirement, social inclusion, family relationships, healthdevelopment and the need for help and care among the oldest old. The study didcontinue from 2010 through to 2012. This update has not only enhanced thePSAE’s longitudinal capacity, but also enabled a range of analyses related toissues of change and causal relationships to be undertaken.

A Review of Longitudinal Datasets on Ageing11The Survey of Health, Ageing and Retirement in Europe (SHARE) is amultidisciplinary and cross-national panel database of micro data on health,socio-economic status and social and family networks of more than 55,000individuals from 20 European countries aged 50 or over.SHARE seeks to analyse the process of population ageing in depth. It is thefirst study to examine the different ways in which people aged 50 and older livein 20 European countries from Sweden to Greece and Portugal to Estonia. Itsscientific potential lies in the extensive data gathered from more than 60.000people all across Europe, covering the interplay between economic, health, andsocial factors in shaping older people’s living conditions (SHARE. dmin/SHARE Brochure/sharebroschuere webfinal.pdf).The Irish Longitudinal Study on Ageing (TILDA) is a study of a representativecohort of over 8500 people resident in Ireland aged 50 , charting their health,social and economic circumstances over a 10-year period commencing late 2009.TILDA is unique amongst longitudinal studies internationally in the breadth ofphysical, mental health and cognitive measures collected.Two new studies are currently under development in Scotland and Brazil.The Scottish Longitudinal Study of Ageing (THSLS) is in its planning stages.A scoping study was undertaken in 2008 aimed at evaluating the costs andbenefits of carrying out an ageing survey in Scotland similar but not identical toELSA, TILDA or SHARE. (Anderson, Boyle & Sharp 2008). It was concludedthat current datasets do not provide enough relevant information to study in asystematic and meaningful way population ageing in Scotland. It also concludedthat given the unique nature of Scotland’s demography and potential policydifferences brought about by devolution a specific study is warranted. It hasreceived funding from the Economic and Social Research Council, Centre forPopulation Change and the Scottish Institute for Research in Economics. Anapplication to the National Institute for Aging for a pilot study is under review.The ten year study aims to interview around 10,000 individuals every 2 yearsalong with a full medical examination. Individuals older than 45 years will beincluded in the sample. This is a younger starting age than most ageing studiesbut is justified by the relatively poorer health experience in Scotland compared tomost other high income countries. The study plans to innovate in several areas.For example, the nature of the health service in Scotland makes it possible tomatch into the survey data detailed information from hospital and physicianrecords. Physical activity will be carefully monitored through accelerometers andGPS devices. Information will continue to be collected when sample membersleave their homes and enter institutions. “Cloud data” methods and tabletcomputing technology will be used to collect information between interviews(Wright 2012).The Brazilian Longitudinal Study of Ageing (ELSI-Brasil) ELSI-Brasil whichwill be based on ELSA is also under development with the support of the BrazilianMinistry of Health and the National Institute on Aging (NIA/NIH) in the US andintends to be launched in 2013. Compared to the Scottish study, it is looking atincluding nationally representative samples of an older age cohort, those aged50 years of age with an even more ambitious number of interviews at 15,000

12A. Kaiserconsisting of household interviews every 2 years, annual telephone interview and anurse visit every 4 years. The main aims of ELSI-Brazil are: to provide datanecessary for the exploration of the unfolding dynamic relationships between healthand functioning, economic position, social participation/networks and well-being,as people plan for, move into and progress beyond retirement; to investigateseparate and joint effects of environmental and genetic factors on health outcomes(highly mixed population: African, European and Native American ancestry); toinclude strategic themes for the Brazilian government: i.e. the impact of publicpolicies (public pensions and the Unified Public Health System); to improve wellbeing and health conditions and to reduce social inequalities; and to enableinternational comparisons (harmonization) (Oliveira 2012)Methodology (Sampling, Design, Timeframes, Method of Collection)Methodological development was as wide ranging as to the aims of the studies andwas dependent on the outcomes required. Sample sizes and diversity were based on anumber of factors including geographic location, health condition, economic status,and so on which was further complicated by some studies interviewing not only theelderly respondents but their families and household members. This was furthercomplicated by the fact that when new waves for studies were conducted theysometimes also amended the questions, intentions and made up for the attrition byrecruiting additional subjects. One final factor was the frequency in which the follow-uptook place (Table 2).Benefits & Key FindingsOverall the benefits realised in each individual study were a much clearer snapshot ofthe issues reflecting the ageing society in the country or countries in which the studywas undertaken. The data served as the source for hundreds of publications, policyand working papers, created new lines of inquiry and created a baseline for governments, institutions and individuals to project and follow the issues of their nationalageing populations and compare it to other countries. More specifically:ALSA - The material collected during the ALSA comprises the most comprehensive longitudinal data base yet assembled on ageing Australians and it complementsin a unique way those available internationally. The findings of the ALSA aredirectly relevant to policy formulation and planning of health and social services foran ageing population. Researchers have reported on the Australian LongitudinalStudy of Ageing in over 200 publications including reports, book chapters, refereedjournal articles, abstracts, conference proceedings and theses. Recent funding fromthe Australian Research Council’s Discovery Projects Scheme will also enable amultidisciplinary team of researchers to study Adelaideans over the age of 85, alsoreferred to as the ‘oldest old’. This data will be combined with ALSA data collectedpreviously to enable the dynamics of ageing to be revealed, i.e. it will lookprospectively at risk and protective factors associated with ageing well. The ALSAhas also been integral to a project funded by the Premiers Science Research Fund.

A Review of Longitudinal Datasets on Ageing13Table 2 Methodological comparisonDatasetsMethodology appliedNumber of wavesALSAComprehensive personalinterviews, functionalassessment, self-completionquestionnaire, telephoneinterviewsWave 1 to 111992–2010Waves 12Scheduled 2013Wave 13Scheduled 2014Computer assisted interviews(CAPI), health statusassessment, collectionof biomarkersBaseline2008Wave 12011Wave 22013ComprehensiveQuestionnaires, TrackingQuestionnaires, PhysicalAssessments, BiospecimensBaseline2008Interviews, health statusassessment, life-historyinterviewWave 1 - Interview2002–2003Wave 2 - Interview &Nurse visit2004–2005Wave 3 Interview & Lifehistory interview2006–2007Wave 4 Interview Nursevisit2008–2009Wave 5 Interview2010–2011CHARLSCLSAELSADatesFollow up every 2 yearsfor 20 yearsGLASSelf-completion questionnaire(individuals & employers)Three waves2005–2008HILDAHousehold questionnaire,Individual Self-completionQuestionnaireWave 12001Wave 2 – householdwealthWave 3 - RetirementWave 4 – Health Insurance& youthWave 5 – Fertility,expenditures, intentionsWave 6 – HouseholdwealthWave 7 – Retirement,HealthWave 8 – FertilityWave 9 – Immigration,Health, DietWave 10 – Householdwealth, intentionsWave 11 - FertilityHRSMixed mode design includingindividual interviews inperson or by telephone aswell as mail and internetquestionnaires, collection ofbiomarkers and geneticinformationMost recent wave tookplace in February 20121992, 1993, 1994,1995,1996, 1998,2000, 2002, 2004,2006, 2008, 2010,2012

14A. KaiserTable 2 (continued)DatasetsMethodology appliedNumber of wavesDatesILSAPersonal interviews, healthassessment (physical exams,laboratory tests)Baseline examination1992-1993Second examination1995Self-completion questionnaire& computer assisted personalinterviews (CAPI)Baseline survey2007Follow up2009CAPI interviews, collection ofbiomarkers, measurement ofwellbeing.Wave 12006 & 2007Wave 22008 & 2009Wave 32010Comprehensive personalinterviews (individual &household), CAPI interviews,collection of biomarkers,measurement of wellbeingPilot2010Wave 12012Comprehensive personalinterviews, collection ofbiomarkers, measurement ofwellbeingBaseline survey2001 and 2003PSAEQuestionnaires, measurementof living conditions andwellbeingCo-ordinated with StatisticSweden’s annual surveyon living conditions2002 – 2003SHARECAPI interviews & selfcompletion questionnaire,collection of biomarkers,measurement of wellbeing,all components translatedinto all languages ofparticipating countriesWave 1 (12 countries)2004/2005Wave 2 (15 countries)2006/2007Wave 3 (13 countries)2008/2009CAPI interview & selfcompletion questionnaire,full health assessment(home & centre based),measurement of wellbeingJSTARKLOSALASIMHASTILDA2012Scheduled 2014Wave 4 (16 countries)2010/2011Wave 52012/2013Wave 12009–2011Wave 22012Wave 3Scheduled 2014Wave 4Scheduled 2016Wave 12012–2013 Dependenton availability offundingUnder developmentELSI - BrasilPlan include comprehensivepersonal interviews,telephone interviews,collection of biomarkers,measurement of wellbeingTHSLSIn designing study, idealmethodology to be usedwill be CAPI, followed byin-home nurse interview.Other considerations includetelephone, postal orweb-based questionnaires.Life of survey will beminimum 10 years.The South Australian Population Health Intergenerational Research (SAPHIRe)project will provide valuable new insights into the complex factors that contribute

A Review of Longitudinal Datasets on Ageing15to positive and negative health outcomes for people from childhood through toold age.CHARLS – The study has been instrumental in providing vital information for thegovernment to develop policy, particular in the areas of health and security andassisted in the long-term tracking of “The Twelfth 5-year Planning” and healthcarereform. Providing this in-depth understanding of the relationships between elderlyhealth, social security and economic status has proven helpful to the developmentand evaluation of government policies. In the area of health care, it has enhancedthe ability to monitor chronic diseases and analyse policies through the provision ofdetailed data on the heavy burden of disease prevalence on ageing people and itsimpact on the country’ economic development.The extensive output has encompassed reports on a variety of topics suchas effects of China’s pensions system; health care utilisation; elderly livingarrangements; and land productivity (CHARLS 2012).CLSA - is a large, national, long-term study of adult development and aging. Thelongitudinal design and extended follow-up will provide a unique opportunity toexamine health transitions and trajectories over time, with the goal of betterunderstanding the complex interplay among the vast array of determinants ofhealth, from gene-environment interactions to transitions to retirement. TheCLSA will advance ageing research in Canada and enable researchers to movebeyond providing a snapshot of the adult Canadian population toward observingand understanding the evolution of diseases, psychological attributes, function,disabilities, and psychosocial processes that frequently accompany aging. Thisinformation is critical to prepare for 2026 at which time one in five Canadianswill be 65 or older (CLSA 2009).ELSA – ELSA is the first representative longitudinal study of older people inEngland to have a well-integrated multidisciplinary approach that is equallystrong in measuring economic, health and social aspects of people’s lives, withsuch a strong joint emphasis on detailed economic processes and the assessmentof all elements of health processes including symptoms, subjective assessments,diagnoses and biomarkers. Innovative techniques for estimating income andwealth have greatly strengthened the scope for obtaining comprehensive dataon financial circumstances in a phase of life that is difficult to quantify in termsof simple indices of income. The harmonization of ELSA with other nationalstudies of ageing has facilitated international comparisons, while linkage toadministrative data has added great analytic power to the study. The age distributionof the cohort means that disability, disease and mortality emerge at a substantialrate, facilitating longitudinal analyses of health outcomes and these are strengthened by the inclusion of objective markers of health, physical and cognitiveperformance and biology. The detailed psychosocial and economic phenotypinghas presented opportunities for geno-economics. The rapid availability of data tothe general research community overcomes the time delays present for many cohortstudies and ensures that up to date information can be analysed. The study hasresulted in more than 165 publications, with 59 alone during 2011 and 2012.The highly ranked publications reflect the extensive variety of topics covered bythe study including disease; health literacy; and coronary artery disease prevention(ELSA 2011).

16A. KaiserGLAS - In the first wave of the Global Ageing Survey funded by HSBC in 2004,approximately 11,000 persons aged 18 years and over in 10 countries and territoriesacross four continents were surveyed on a variety of issues relating to ageing andlater life. That first wave revealed that people’s attitudes to ageing and later life werepredominantly positive across the globe. In addition, people’s expectations in respectof withdrawal from the labour market proved to be more flexible and forwardlooking than labour market infrastructures often allow. The interplay between individuals, families, workplaces and government is complex, and the first wave of thesurvey showed that this is no less so in later life. Thirty years down the line, thosesame governments and workplaces are struggling to encourage us to delay ourdeparture from the workplace. But how do these societal and workplace needscompare with the expectations and aspirations of the people? And are employersin tune these expectations and aspirations? The Global Ageing Survey was able toprovide significant insight into how peoples and businesses worldwide are meetingone of the 21st century’s greatest challenges in addition to identifying other keyquestions which need to be investigated (Harper and Leeson 2006).HILDA - Research applications of HILDA data have successfully covered fourmain topic areas. The first is in the area of transformation of family andhousehold structure. This data has added to the knowledge about economicconsequences of marital relationships, impact of divorce, patterns of cohabitationand quality of living a

2006, to create the basic data needed to devise and implement effective social, economic policies to address the trends that emerge in the process of population ageing. Its aim was to collect information on work and income and health and disability and includes detailed questions on family transfers. This statistical data