The Wisconsin Longitudinal Study: Designing a Study of the Life Course 1 Robert M. Hauser Vilas Research Professor of Sociology University of Wisconsin-Madison August 28, 2008 Introduction The Wisconsin Longitudinal Study (WLS) is just over 50 years old, and it has become the most enduring study of its scope and size in the United States and, perhaps, in the world. What began as a state-inspired survey in the late 1950s of what happens to Wisconsin youth after high school has become a biosocial study of health, cognition, and well-being in the retirement years as well as a vehicle for studies of intergenerational social and economic stratification. A lone investigator at the University of Wisconsin-Madison has been replaced by a loosely coordinated team of several dozen researchers that spans the nation. A once-private and distinctly modest data resource has evolved into a complex combination of survey operations and administrative record links with a web-based system for public distribution of massive data files, extensive documentation, powerful search and extraction tools, and hundreds of publications. 2 The importance of the WLS as a resource for studies of the life course depends on the extensive data that have been collected from 1957 onward – or even earlier in some cases – and on the investments that the National Institute on Aging has made in the study since the early 1990s (Sewell, Hauser, Springer, & Hauser, 2004). The WLS can contribute to basic knowledge about social, behavioral, and biological processes in three fundamental ways. The first is by providing new information about the consequences of childhood and adolescent conditions and experiences. A second major contribution of the WLS is to provide new information about the
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The Wisconsin Longitudinal Study:
Designing a Study of the Life Course1
Robert M. Hauser
Vilas Research Professor of Sociology
University of Wisconsin-Madison
August 28, 2008
Introduction
The Wisconsin Longitudinal Study (WLS) is just over 50 years old, and it has become the
most enduring study of its scope and size in the United States and, perhaps, in the world. What
began as a state-inspired survey in the late 1950s of what happens to Wisconsin youth after high
school has become a biosocial study of health, cognition, and well-being in the retirement years
as well as a vehicle for studies of intergenerational social and economic stratification. A lone
investigator at the University of Wisconsin-Madison has been replaced by a loosely coordinated
team of several dozen researchers that spans the nation. A once-private and distinctly modest
data resource has evolved into a complex combination of survey operations and administrative
record links with a web-based system for public distribution of massive data files, extensive
documentation, powerful search and extraction tools, and hundreds of publications.2
The importance of the WLS as a resource for studies of the life course depends on the
extensive data that have been collected from 1957 onward – or even earlier in some cases –
and on the investments that the National Institute on Aging has made in the study since the early
1990s (Sewell, Hauser, Springer, & Hauser, 2004). The WLS can contribute to basic knowledge
about social, behavioral, and biological processes in three fundamental ways. The first is by
providing new information about the consequences of childhood and adolescent conditions and
experiences. A second major contribution of the WLS is to provide new information about the
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extent to which early life conditions affect later life outcomes, above and beyond the known
effects of the conditions and experiences of adulthood. Finally, because of its rich, complete, and
contemporaneous records of careers and family events – the WLS provides unique opportunities
to analyze the characteristics of whole-life trajectories that may affect the quality and length of
later life.
Today’s research and policy environments are far different from those of the late 1950s.
On the one hand, both the feasibility and the scientific value of longitudinal studies of the life
course are well established. Such studies have become the backbone of observational research in
psychology, sociology, and economics. In the realms of human development and health, by dint
of the well-known Barker hypothesis (Barker, 2001; Kuh & Ben-Shlomo, 1997), life course
research now extends back into the womb, and a national study of child development aims to
follow health and development from couples’ childbearing intentions to offspring at age 21. In
each decade since the 1970s the National Center for Education Statistics has followed a cohort of
youth from secondary school to the end of the school years. The Bureau of Labor Statistics has
fielded three waves of longitudinal studies of adolescent youth since the late 1960s. The National
Institute on Aging supports longitudinal studies of aging in the U.S. – including the WLS – and
in many foreign nations, but its premier data resource, the Health and Retirement Study, now
provides continuous longitudinal coverage of the U.S. population aged 50 and above.
In current and future work, the WLS will be used to explore the implications of the
changing social, political, economic, and technological contexts of the early 21st century for the
well being of a large cohort of men and women transitioning to old age. Among the most
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important social and economic changes is the deinstitutionalization and individualization of
retirement. That is, retirement is no longer a well-defined economic status—simply a matter of
leaving the labor market—but rather a distinct and expected, but highly variable stage of the life
course in which time spent in paid work tends to decline and may be replaced by unemployment,
leisure, or disability.
Over the past 20 years, both the government and employers have shifted more of the
responsibility associated with planning and managing the retirement years towards individuals.
The capacity of individuals to make good choices about their investments, medical care,
insurance, and other domains of increased uncertainty and personal responsibility will be an
important determinant of both financial and health-related well-being in old age. Moreover,
technological advances – ranging from the expansion of the Internet to the development of life-
extending medical technologies– also offer older adults an unprecedented number of options
about health insurance, choice of health care providers, and types of medical treatments. The
contexts in which people are making these choices will play a significant role in shaping the
quality of those choices, and ultimately, in the quality of life for older Americans.
Among other questions, WLS data will be used to ask, “What are the psychological,
cognitive, social, and health contexts in which WLS graduates are planning for and then actually
managing health and financial arrangements in the retirement years?” In short, what kinds of
resources and constraints frame the process of their decision making? Because decisions about
the retirement years are increasingly in the hands of individuals, it is critical that we adequately
understand the contexts that shape peoples’ lives. How do these provisions affect the lives of
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their survivors in the event of their death? A second, key question is, “What are the earlier life
factors, both individual and contextual, that lead to better outcomes in the post-retirement
years?” How is the quality of later life affected by childhood circumstances and their
repercussions across the life course? Are there lagged effects of early life conditions, or of job
and familial trajectories across the life course, or are circumstances in the later years connected
to childhood only through intervening circumstances? We expect that analyses of the cumulated
WLS survey and biomarker data, along with rich administrative and public data, will resolve old
questions and open new areas of interdisciplinary inquiry about health, aging, and the life course.
I wish that I could write that the evolution of the WLS followed a well-established plan,
or at least an aspiration, that from the outset the WLS was intended to track the entire life course
of thousands of Wisconsin youth and to become a resource for a research team in Madison and
for hundreds of other researchers across the globe. But in the late 1950s there was no such
intention, nor were there appropriate theoretical or methodological templates for such an
endeavor. Rather, the study has been like Topsy: “It just grew.” To be less flippant, the evolution
of the WLS has paralleled that of the human life course; it began and has changed as a
consequence of its initial location in time and place, social and intellectual connections,
individual initiatives, and adaptation across time to external events (Giele & Elder, 1998). In this
chapter, with its focus on the development of the WLS, I will draw repeatedly on this parallel,
but more important, I will try to highlight some of the decisions – regarding content, design, and
method – that have shaped the project.
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The Wisconsin Longitudinal Study: Its Origin and Research Context
The Wisconsin Longitudinal Study (WLS) began with a 1957 survey of the educational
plans of all high school seniors in the public, private, and parochial schools of Wisconsin. Not
only was there a rising demand for college and university education in the late 1950s, but also
economic and technological competition with the Soviet Union was a major public issue. Many
states, including Wisconsin, were then consolidating and upgrading their post-secondary
educational institutions. At that time, most of the units of the present University of Wisconsin
System were state and county teachers colleges. J. Kenneth Little, Professor in the School of
Education at the University of Wisconsin, conducted the statewide survey with the cooperation
of the Wisconsin State Superintendent of Schools, and it was used to plan the expansion and
consolidation of public higher education in the State (Little, 1958, 1959).
In 1962, William H. Sewell, one of the academic leaders who brought the behavioral and
social sciences into NIH (Sewell, 1988), learned that the 1957 survey schedules and punch cards
were sitting unused in the University administration building. Sewell had long been interested in
the formation and consequences of youthful aspirations, but he had lacked access to an
appropriate population for study. At that time, social scientists had little real evidence about the
extent of social and economic mobility between generations in the United States. Only in 1962
was the first large national study of social mobility in America conducted (Blau & Duncan,
1967). Researchers could do little more than speculate about the processes of selection and
socialization that accounted for social stability or social movement.
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Sewell selected a random, one-third sample of the graduates, consisting of 10,317 cases,
for further study. He then added information on the measured mental ability of each student from
files of the Wisconsin State Testing Service, which had, since 1929, conducted a testing program
covering all high school students in the state (Froehlich, 1941; Henmon & Holt, 1931; Henmon
& Nelson, 1946, 1954). While Sewell’s collection of the test score data followed naturally from
his interest in post-secondary educational entry and completion, that measure has proved to be
one of two key variables that have sustained the value of the WLS data. Moreover, the files of
the State Testing Service have subsequently provided test scores for other participants in the
study, including siblings of the graduates and spouses of the graduates and siblings.
Sewell developed a number of indexes based on information from the survey—including
the socioeconomic status of the student’s family, the student’s attitudes toward higher education,
educational and occupational plans, and perceived influence of significant others on educational
plans—and then added these to each student’s card. Finally, using secondary sources, he
constructed relevant measures of school, neighborhood, and community contexts. These included
the socioeconomic composition of each senior class (Sewell & Armer, 1966a, 1966b, 1972), the
percentage of its members who planned on going to college, the size of the school, the size and
degree of urbanization of the community of residence, and the distance of the student’s place of
residence from the nearest public or private college or university (Anderson, Bowman, & Tinto,
1972). However, the second key variable in the WLS was a four-year average of parents’
incomes from 1957 to 1960 that Sewell was able to obtain from files of the Wisconsin
Department of Revenue; unlike many other longitudinal studies, up to the present day, he
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obtained a direct and highly reliable measure of economic standing in adolescence. Thus began a
research program that is in its sixth decade and that now focuses on the life-long antecedents of
health and aging.
In the early years WLS research focused mainly on the ways in which adolescent
achievements and aspirations were formed and then influenced post-secondary schooling and
occupational careers. This work led to the so-called “Wisconsin Model of Status Attainment”
(see Figure 2.1), which became a template for subsequent research on the life course – and for
critical attention to the social psychological theory of status attainment (Sewell, Haller, &
Porter, J. N. (1974). Race, Socialization and Mobility in Educational and Early Occupational
Attainment. American Sociological Review, 39(3), 303-316.
Portes, A., & Wilson, K. (1976). Black-White Differences in Educational Attainment. American
Sociological Review, 41(3), 414-431.
Reiss, A. J., Jr., & Rhodes, A. L. (1961). The Distribution of Juvenile Delinquency in the Social
Class Structure. American Sociological Review, 26(5), 720-732.
Reither, E. N., Hauser, R. M., & Swallen, K. E. (forthcoming). Predicting Adult Health and
Mortality from Adolescent Facial Characteristics in Yearbook Photographs.
Demography.
Rhodes, A. L., Reiss, A. J., Jr., & Duncan, O. D. (1965). Occupational Segregation in a
Metropolitan School System. American Journal of Sociology, 70(6), 682-694.
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Rylander-Rudqvist, T., Hakansson, N., Tybring, G., & Wolk, A. (2006). Quality and Quantity of
Saliva DNA Obtained from the Self-administrated Oragene Method--A Pilot Study on the
Cohort of Swedish Men. Cancer Epidemiol Biomarkers Prev, 15(9), 1742-1745.
Sewell, W. H. (1988). The Changing Institutional Structure of Sociology and My Career. In M.
W. Riley (Ed.), Sociological Lives (pp. 119-143). Newbury Park, California: Sage
Publications.
Sewell, W. H., & Armer, J. M. (1966a). Neighborhood Context and College Plans. American
Sociological Review, 31(2), 159-168.
Sewell, W. H., & Armer, J. M. (1966b). Reply to Turner, Michael, and Boyle (On Neighborhood
Context and College Plans [I], [II], [III]). American Sociological Review, 31(5), 698-712.
Sewell, W. H., & Armer, J. M. (1972). High School Context and College Plans: A Comment.
American Sociological Review, 37(5), 637-639.
Sewell, W. H., Haller, A. O., & Ohlendorf, G. W. (1970). The Educational and Early
Occupational Status Attainment Process: Replication and Revision. American
Sociological Review, 35(6), 1014-1027.
Sewell, W. H., Haller, A. O., & Portes, A. (1969). The Educational and Early Occupational
Attainment Process. American Sociological Review, 34(1), 82-92.
Sewell, W. H., & Hauser, R. M. (1972). Causes and Consequences of Higher Education: Models
of the Status Attainment Process. American Journal of Agricultural Economics, 54(6),
851-861.
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Sewell, W. H., & Hauser, R. M. (1975). Education, Occupation, and Earnings: Achievement in
the Early Career. New York: Academic Press.
Sewell, W. H., & Hauser, R. M. (1992). The Influence of The American Occupational Structure
on the Wisconsin Model. Contemporary Sociology, 21(5), 598-603.
Sewell, W. H., Hauser, R. M., Springer, K. W., & Hauser, T. S. (2004). As We Age: The
Wisconsin Longitudinal Study, 1957-2001. In K. Leicht (Ed.), Research in Social
Stratification and Mobility (Vol. 20, pp. 3-111). London: Elsevier.
Sewell, W. H., Hauser, R. M., & Wolf, W. C. (1980). Sex, Schooling and Occupational Status.
American Journal of Sociology, 86(3), 551-583.
Terman, L. M. (1925). Mental and Physical Traits of a Thousand Gifted Children. Stanford,
California: Stanford University Press.
Terman, L. M., & Oden, M. H. (1959a). The Gifted Child Grows Up: Twenty-Five Years'
Follow-Up of a Superior Group. Stanford, California: Stanford University Press.
Terman, L. M., & Oden, M. H. (1959b). The Gifted Group at Mid-Life: Thirty-Five Years'
Follow-Up of the Superior Child. Stanford, California: Stanford University Press.
Turner, R. H. (1960). Sponsored and Contest Mobility and the School System. American
Sociological Review, 25(6), 855-867.
Turner, R. H. (1964). The Social Context of Ambition. San Francisco: Chandler.
University of Pittsburgh, P. T. O. (1964). The American high-school student the identification,
development, and utilization of human talents. Pittsburgh.
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University of Pittsburgh, P. T. O. (1966). Project Talent; one-year follow-up studies. Pittsburgh:
School of Education, University of Pittsburgh.
Wadsworth, M. E. J. (1991). The Imprint of Time: Childhood, History, and Adult Life. Oxford:
Clarendon Press.
Warren, J. R., Sheridan, J. T., & Hauser, R. M. (2002). Occupational Stratification Across the
Life Course: Evidence from the Wisconsin Longitudinal Study. American Sociological
Review, 67(3, June), 432-455.
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Figure 2.2. Survey and Administrative Record Data in the Wisconsin Longitudinal Study
Sources of Survey Data: $ 1957 Senior Survey of Graduates $ 1964 Postcard Survey of Parents $ 1975 Telephone Survey of Graduates $ 1977 Telephone Survey of Siblings $ 1993 Telephone/Mail Survey of Graduates $ 1994 Telephone/Mail Survey of Siblings $ 2003-07 Telephone/Mail Surveys of Graduates, Siblings, Spouses, and Widows $ 2007 Mail Survey about Medicare Part D enrollment $ 2009-10 Personal Home Interviews and Assessments (in development) Available Public or Administrative Record Data: $ Henmon-Nelson Mental Ability (9th and 11th grades for graduates, other years for
siblings and spouses) $ Rank in High School Class $ High school yearbooks (including senior-year photos and extra-curricular activities) $ Parents' Adjusted Gross Income, 1957-60 $ Male Graduate's earnings, 1957-71 $ College Characteristics $ Employer Characteristics, 1975 $ National Death Index-Plus (and Social Security Death Index) $ Elementary and high school resources (from Wisconsin state archives) $ Wisconsin health insurance plans $ Local health resources (Area Resource File and Interstudy data) $ Medicare enrollment and claim data (at present, only for older siblings) $ Wisconsin Worker's Compensation records
Biomarkers
DNA samples (graduates in 2007, siblings in 2008) Administrative Record Data in Process: $ Wisconsin state tumor registry $ Geocoded addresses across the life course
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1 The research reported herein was supported by the National Institute on Aging (R01 AG-9775 and P01-AG21079)
and by the William Vilas Estate Trust. I thank my colleagues – students, staff, and faculty – on the Wisconsin
Longitudinal Study over the decades, especially those from whom I have gleaned parts of this text, but most of all,
the many thousands of research participants whose generosity and trust has made the WLS possible. The opinions