Every 2 years, thousands of older Americans tell their stories. Quietly, compellingly, they answer questions about every aspect of their lives-how they are feeling, how they are faring financially, how they are interacting with family and others. They do this as participants in the U.S. Health and Retirement Study (HRS), one of the most innovative studies ever conducted to better understand the nature of health and well-being in later life. The HRS's purpose is to learn if individuals and families are preparing for the economic and health requirements of advancing age and the types of actions and interventions-at both the individual and societal levels-that can promote or threaten health and wealth in retirement. Now in its second decade, the HRS is the leading resource for data on the combined health and economic circumstances of Americans over age 50.
During each 2-year cycle of interviews, the HRS team surveys more than 20,000 people who represent the Nation's diversity of economic conditions, racial and ethnic backgrounds, health, marital histories and family compositions, occupations and employment histories, living arrangements, and other aspects of life. Since 1992, more than 27,000 people have given 200,000 hours of interviews.
The HRS is managed jointly through a cooperative agreement between the National Institute on Aging (NIA) and the Institute for Social Research (ISR) at the University of Michigan. The study is designed, administered, and conducted by the ISR, and decisions about the study content are made by the investigators. The principal investigators at the University of Michigan are joined by a cadre of co-investigators and working group members who are leading academic researchers from across the United States in a variety of disciplines, including economics, medicine, demography, psychology, public health, and survey methodology. In addition, the NIA is advised by a Data Monitoring Committee charged with maintaining HRS quality, keeping the survey relevant and attuned to the technical needs of researchers who use the data, and ensuring that it addresses the information needs of policymakers and the public. Since the study began, 7,000 people have registered to use the data, and nearly 1,000 researchers have employed the data to publish more than 1,000 reports, including more than 600 peer-reviewed journal articles and book chapters, and 70 doctoral dissertations. Figure A-1 shows that the number of studies using HRS data has grown rapidly as the scientific community becomes more aware of the richness and availability of the HRS data.
In the coming years, the NIA seeks to expand even further the use of the HRS database, viewed by the Institute and experts worldwide as a valuable national research resource in aging. This publication seeks to engage new audiences of scientists, policymakers, media, and other communities with an interest in aging to use this treasure trove of data, by showcasing how the HRS can help examine the complex interplay of health, economic, and social factors affecting the lives of older people and their families.
The chapters are organized into several broad themes. This introduction presents an overview of the HRS objectives, design, content, and uses. Subsequent chapters present content on health, work and retirement, income and wealth, and family characteristics and intergenerational transfers. Data highlights are presented throughout.
The HRS collects data to help:
Designed over 18 months by a team of leading economists, demographers, psychologists, health researchers, survey methodologists, and policymakers, the study set out to provide each of these sciences with ongoing data collected in a methodologically sound and sophisticated way. Figure A-2 indicates the share of time during the hour-plus HRS interview that is devoted to three broad areas of inquiry-economics, health, and family. Within these categories, the HRS specifically focuses on:
The HRS collects detailed information about older Americans' economic circumstances-sources and amounts of income; the composition and amounts of assets; and entitlements to current and future benefits such as those provided through Social Security, Medicare, Medicaid, employer pension plans, and employer-sponsored health insurance. Data describing the movement of assets, including gifts and bequests, time (e.g., to provide daily living assistance), and housing within families, are also collected, as are data about earnings, savings, and spending of individuals and families as they approach retirement and over the course of their retirement until death.
|Year||Journal Article||Book/Book Chapter||Dissertation||Working Paper||Total|
Occupation and employment information collected by the HRS covers job characteristics, job mobility, work hours, attitudes toward retirement, employer-provided benefits (including health insurance, pensions, 401(k) plans, and other employer-sponsored saving programs), retirement benefits, and early retirement incentive offers.
The HRS collects information about chronic illness, functional ability, depression, and self-assessed health status, and examines health-related behaviors such as smoking, alcohol use, and exercise. Health care utilization data gathered through the study describe physician visits, hospitalizations, nursing home stays, surgeries, dental care, prescription drug use, use of assistive devices (e.g., eyeglasses and walkers), and receipt of caregiving services, as well as health and long-term care insurance coverage, out-of-pocket medical costs, and receipt of assistance with medical expenses.
In the 2006 data collection, the HRS expanded to include biological information about the participants in an updated effort to match biological factors with health and social data. This new effort records participants' height and weight, measurements of lung function, blood pressure, grip strength, and walking speed. It also collects small samples of blood to measure cholesterol and glycosylated hemoglobin (an indicator of blood sugar control) levels, and DNA from salivary samples for future genetic analyses.
The HRS is unique among large surveys in its use of direct measures of cognition, drawn from established clinical instruments. These measures provide invaluable data on cognitive change with aging and the impact of dementia on families. They have also found new application in studies of economic behavior and survey response patterns.
The survey explores the relationships between people's living arrangements and the availability or use of long-term care services such as nursing home residence, services offered to residents living in other housing arrangements, and special housing features for people who are physically impaired. It also gathers data about the type of housing structure in which HRS participants live, housing ownership or financial arrangements, entry fees or association payments, and the sharing of housing with children or others.
The HRS gathers standard demographic facts such as age, racial/ethnic background, education, marital status and history, and family composition. Among married participants, detailed health and economic information is collected from both spouses. General demographic information about HRS participants' parents, children, and siblings is also gathered. In addition, survey interviews document the relationships among family members and the nature of intergenerational family supports, including financial transfers, caregiving, joint housing arrangements, and time spent with family members.
The research team that designed the HRS made a number of difficult decisions about how many people to include in the survey, whether to survey the same people over time or to survey new participants, how often to conduct interviews, and what questions to include in the interviews. The outcome of these decisions is a "steady state" model that:
This design allows researchers to use the data in a number of important ways:
Regular re-interviews with HRS participants are an essential feature of the survey design. Analysts can follow individuals' evolving circumstances and answer general questions about what happens in families as their members age. For example, analyses of the data can reveal the extent to which people spend down their assets as they age, find out whether people hold steady employment or move into and out of the labor force, and assess the dynamics of health deterioration and improvement with age. Further important questions to be explored ask: What are the circumstances leading up to major life transitions such as retirement or health events? How do people respond to those transitions? What are the consequences of those transitions?
The HRS is a rich resource for exploring national trends in health and economic status over time. It allows for examination of cohort differences, for example, by comparing the characteristics and behavior of 61-year-olds in 1992 with the characteristics and behavior of 61-year-olds in 2002. The data can show whether people have more or fewer financial assets now than in previous years, are more or less likely to work, and are more or less likely to be caring for an aging parent or providing childcare for a grandchild. Analysts can also track trends in age-adjusted health and function, and they can investigate whether or not smoking, alcohol use, and fitness behaviors are changing. Use of the survey to study trends over time depends less on following individuals as they age and more on comparisons of similarly situated individuals at different points in time.
By representing the U.S. population as a whole, the HRS provides researchers a way to examine and compare circumstances across income, racial/ethnic, gender, and other subgroups. For example, the financial resources of people with the least income and those at the median and in the highest income bracket can be compared. The data can be used to contrast outcomes for people who have suffered heart attacks with those of people who develop diabetes, dementia, arthritis, or cancer. They also permit targeted analyses of the characteristics of people whose health status or poverty may make them particularly vulnerable, including the study of how well government safety nets protect vulnerable individuals. The data further can look at differences among married and unmarried people; those with and without children; and those who retire young, who retire at typical ages, and who continue working past standard retirement ages.
The HRS survey design supports analyses of what causes things to happen. Collection of such a wide range of information about families over time enables analyses of how older adults' circumstances change and how one dimension of their lives relates to other dimensions. For instance, it is interesting that many Americans choose to retire at relatively young ages, but critical questions for policymakers are why people retire young and whether they can support themselves over the course of long retirement spans. As HRS data accumulate over time, scientists hope to understand better a broad array of causal issues. For example, the HRS data might be used to determine specifically why some older Americans fall into poverty, the propensity for certain smokers to quit while others continue smoking, factors that lead some people to leave large bequests and others none, the effect of employer-provided health insurance or "Medigap" insurance on retirement decisions or the use of medical services, and why people with similar functional ability choose different living arrangements and different forms of care. The data can also be used to explore the reasons why some people save far more than others, even if they have equivalent salaries and life circumstances. Additionally, HRS analyses can identify obstacles that delay retirement in order to pay for the extra years of life, given the rise in life expectancy and improved health.
Armed with some knowledge of causality, researchers can use the HRS data to simulate what might happen under different policy scenarios and the likely implications of aging-related policy reforms. For example, they can ask: What will happen to decisions about work at older ages as the earnings test on Social Security benefits is eliminated? What would happen to retirement decisions if the age of eligibility for early Social Security benefits were increased from 62 to 65? To what extent would the economic circumstances of widows be affected if Social Security survivorship benefits were increased? What is the impact of the new Medicare Part D prescription drug benefit? What would happen to saving rates if the contribution limits on individual retirement accounts were raised?
Among the HRS's important contributions to the study of aging and to social science research:
The HRS is unique because of several survey innovations. These include:
Surveys asking about income and assets historically have been troubled by participants' refusal to answer financial questions or inability to answer them knowledgeably. Further, many surveys also have not accounted for major components of assets or income and/or have used measures that do not truly reflect assets and income. The HRS has made major advances in both of these areas. The study developed a technique known as "random-entry bracketing," which reduces the number of nonresponses by eliciting ranges of values from respondents who would otherwise give no information at all. To improve the measurement of income from assets, the survey brought together questions about the ownership of certain assets (e.g., stocks and bonds) and the income obtained from those assets. In addition, traditional measures of income and wealth have been integrated with detailed data about Social Security, pensions, and other future entitlements-a significant accomplishment of the HRS, particularly because future entitlements represent a major component of the financial status of older Americans. These new methods have been widely adopted by many other surveys.
The decisions people make as they age are influenced not only by past and current circumstances, but also by what they expect to happen in the future. Most surveys focus on measuring current circumstances and, to some extent, what people can remember about the past. An exciting innovation in the HRS is the exploration of participants' future expectations. This novel approach yields valuable information about how long people how long they will live, the likelihood of giving major financial assistance to family members in the future, whether or not they expect to leave a bequest and the amount of that bequest, and whether they think they will enter a nursing home or move to a new home or other living arrangement in the future. Initial analysis of these data suggests that expectations have an important influence on the decisions that people make.
There are limits to the number of questions that can be asked and answered in a population survey, and there is great value in maintaining that same core of questions in a longitudinal study. Alternative vehicles may be needed, however, to allow researchers to explore narrowly focused topics or test new survey ideas. The HRS uses "experimental modules"-short sequences of questions administered to randomly selected subgroups of participants at the end of the survey. To date, more than 70 experimental modules have asked about physiological capacity, early childhood experiences, personality, quality of life, employment opportunities, use of complementary and alternative medicines, parental wealth, activities and time use, nutrition, medical directives, living wills, retirement expectations and planning, sleep, and functional ability. Appendix A provides more information about these modules.
The HRS by its nature asks questions about some of the most personal and confidential aspects of participants' lives. Nothing is more important to the NIA, the University of Michigan, and the HRS study team than protecting the confidentiality of the respondents and what they have shared. This protection of privacy is also an essential element in ensuring people's participation in this type of extensive, long-term social science survey.
To ensure privacy and confidentiality, all study participants' names, addresses, and contact information are maintained in a secure control file. All personnel and affiliates with access to identifying information must sign a pledge of confidentiality, which explicitly prohibits disclosure of information about study participants.
The survey data are only released to the research community after undergoing a rigorous process to remove or mask any identifying information. In the first stage, a list of variables (such as State of residence or specific occupation) that will be removed or masked for confidentiality is created. After those variables are removed from the data file, the remaining variables are tested for any possible identifying content. When testing is complete, the data files are subject to final review and approval by the HRS Data Release Protocol Committee.
Data ready for public use are made available to qualified researchers via a secure website. Registration is required of all researchers before downloading files for analyses. In addition, use of linked data from other sources, such as Social Security or Medicare records, is strictly controlled under special agreements with specially approved researchers operating in secure computing environments that are periodically audited for compliance. The HRS also obtained a Certificate of Confidentiality from the National Institutes of Health in order to protect the data from any forced disclosure.
Despite the comprehensive nature of the HRS, limitations exist in terms of what can be learned from population interviews. To provide more detailed and elaborate information in particular areas, the HRS team asks participants for permission to link their interview responses to other data resources, as described below. Linked administrative records are available only as restricted data under special agreements with a highly restricted group of individual researchers that guarantee security and confidentiality.
The Social Security Administration keeps detailed records on the past employment and earnings of most Americans. For those who have applied for Social Security payments, records of benefit decisions and benefits paid, including those paid through the Social Security Disability Insurance (SSDI) or Supplemental Security Income (SSI) programs, are available to researchers. By linking these records to HRS participants' interview responses, a significantly richer body of data can be analyzed to better understand the relationships between health and economic circumstances, public and private retirement policies, and the work and retirement decisions that people make as they age.
Through the administration of the Medicare program, the Centers for Medicare & Medicaid Services (formerly the Health Care Financing Administration) maintain claims records for the medical services received by essentially all Americans age 65 and older and those less than 65 years who receive Medicare benefits. These records include comprehensive information about hospital stays, outpatient services, physician services, home health care, and hospice care. When linked to the HRS interview data, this supplementary information provides far more detail on the health circumstances and medical treatments received by HRS participants than would otherwise be available. For instance, these Medicare records will enhance research on the implications of health changes, the influence of health-related behaviors on health, the relationships between health and economic circumstances as they evolve jointly over the course of later life, and the impact of supplementary insurance on medical care decisions.
Data from HRS interviews have been supplemented with information obtained from or about participants' employers, without revealing the identities of HRS participants to employers. One important area of focus is pension plans. While most pension-eligible workers have some idea of the benefits available through their pension plans, they generally are not knowledgeable about detailed provisions of the plans. By linking HRS interview data with specific information on pension-plan provisions, researchers can better understand the contribution of the pension to economic circumstances and the effects of the pension structure on work and retirement decisions.
The HRS began as two distinct though closely related surveys that were merged in 1998 and are administered under the cooperative agreement between the NIA and the University of Michigan's Institute for Social Research. The first study, referred to as the "original HRS," was initially administered in 1992 to a nationally representative sample of Americans between the ages of 51 and 61 (strictly speaking, born in the years 1931 through 1941). In the case of married couples, both spouses (including spouses who were younger than 51 or older than 61) were also interviewed. These participants continue to be contacted every 2 years as part of the ongoing HRS.
The second survey, originally referred to as the Study of Assets and Health Dynamics Among the Oldest Old, or AHEAD, was first administered in 1993 to a nationally representative sample of Americans age 70 and older (strictly speaking, born in 1923 or earlier). Again, in the case of married couples, interviews were conducted with both spouses. About 8,000 people were interviewed as part of the 1993 AHEAD survey. These individuals were re-interviewed in 1995 and 1998, and they, too, continue to be interviewed on the 2-year cycle of the study.
The original HRS and AHEAD surveys were integrated in 1998, and the consolidated project is now referred to as the Health and Retirement Study. Two new groups of survey participants (including spouses) were added in 1998. The first group consists of people in the age group that falls between the original HRS and AHEAD samples. Born between 1924 and 1930 and raised during the Great Depression, these participants are called the Children of the Depression Age, or CODA, cohort. The second group added in 1998 was the first "refresher cohort" brought in to replenish the sample of people in their early 50s as the original HRS cohort aged. It is known as the War Baby cohort, consisting of people born between 1942 and 1947 and their same-age or younger spouses.
Figure A-3 shows the past and projected evolution of the HRS sample, including survey years for the different participant cohorts. In the future, the research team plans to supplement the sample with groups of younger people as they reach their 50s. For example, participants born between 1948 and 1953-the early years of the post-World War II baby boom-were added to the HRS sample in 2004. By continuing to "refresh" the sample, the HRS will provide a long-term source of data on the transition from middle age to the initial stages of retirement and beyond. (For a more complete overview of and background to the development of the HRS, see Juster and Suzman 1995.)
FIGURE A-3 THE HRS LONGITUDINAL SAMPLE DESIGN
No data was available for Figure A-3, which shows the aging of the HRS sample population. Please see text for more information.
Many nations, particularly in Europe, are further along than the United States in population aging, and they have found the multidisciplinary, longitudinal nature of the HRS appealing as a way to obtain a holistic picture of health and retirement trends in their graying populations.
One of the first nations to put such a study in place was Great Britain, where a team of researchers in the late 1990s began planning the English Longitudinal Study of Ageing (ELSA), a survey that is directly comparable to the HRS. ELSA is supported by grants from several departments of the British Government, as well as by the U.S. National Institute on Aging (NIA). The British Government supports ELSA because of its ability to inform both short- and long-term policy options for an aging population. The NIA supports ELSA because of the benefit from comparative analyses of data obtained from people living under very different health and social services arrangements and economic policies. The first rounds of ELSA data were collected in 2002 and 2004, and subsequent waves began in 2006.
The success of the HRS and ELSA has spawned a major international study that now tracks health and retirement trends in Europe. SHARE-the Survey of Health, Ageing and Retirement in Europe-involves Sweden, Denmark, France, Belgium, The Netherlands, Germany, Switzerland, Austria, Spain, Italy, and Greece. Approximately 130 researchers from the participating nations have been organized into multidisciplinary country teams and cross-national working groups, assisted by a number of expert support and advisory teams.
The European study also features many technical innovations designed to maximize cross-national comparability. For example, it employs a single, centrally programmed survey instrument that uses an underlying language database to create country- and language-specific instruments. The initial success of SHARE generated extraordinary interest and led to extending this project to Israel, Ireland, the Czech Republic, and Poland.
Population aging is also becoming a major policy concern in developing countries. The HRS concept is being applied in the Mexican Health and Aging Study (MHAS), the first such effort in a developing country. The MHAS is a prospective panel study of Mexicans born prior to 1951. Its 2001 baseline survey was nationally representative of the older Mexican population and similar in design and content to the HRS. A second round of data collection was undertaken in 2003. In addition to the range of issues that can be considered using HRS data, the MHAS offers an opportunity to explore aging and health dynamics in the context of international migration.
The HRS and SHARE concepts have also been emulated in Eastern Asia. South Korea is already planning the second wave of the Korean Longitudinal Study on Aging, while planning for initial waves is well advanced in China, Thailand, and Japan, and initial planning for an Indian HRS has begun.