Using Survey Data to Study Disability: Results from the National Health Survey on Disability: Volume 3

In spite of the challenges that disability measurement creates in interpretation of results, this volume contains an exciting variety of different types of papers that add not only to our information about persons with disabilities, but also serve as a useful guide to using this extensive data set to address the numerous questions about this population. Following an overview discussion about the development and production of the NHIS-D, this volume has four separate sections. In the first section three papers describing methodological issues in using the NHIS-D are presented. This section includes a paper on factors associated with response patterns (Hendershot et al.) and another on a strategy to overcome the problems of missing data (Witt et al.). The third paper examines disability prevalence by interpreting the NHIS-D data into domains of the ICF classification (Fedeyko & Lollar). The next section contains three papers which focus on work and health care for adults with disabilities (disability measured in different ways), particularly the barriers they experience in those areas. Included in this group are papers on barriers to work (Loprest & Maag), barriers to preventive care (Jones & Beatty), and the effect of insurance as a facilitator and barrier to health care for mobility limited adults (Iezzoni et al.). The third section of four papers focuses on developmental disabilities. Larson et al. discuss the variety of definitions of developmental disability and how those definitions can be operationalized with the measures used in the NHIS-D. Two of the papers examine the outcomes or consequences of childhood disability. Honeycutt et al. focus on the economic costs of developmental disability across the life-span and Maag examines the unmet need for supportive services for this population. Hogan et al. also looks at consequences for siblings of children with disabilities. This section can also be viewed as a methodological one providing a variety of ways to measure developmental disabilities within the same data source. The next section looks at the needs and characteristics of two specific populations; Native Americans (Altman & Rasch), and adult women with MR/DD (Anderson et al.). It also contains a unique approach to understanding the effects of two different aspects of disability, the age of onset of the disability and the proportion of life lived with a disability (Verbrugge & Yang). The book concludes with a discussion of the policy implications of NHIS-D work (Drabeck).

The National Health Interview Survey on Disability, fielded between 1994 and 1997, was one of the most comprehensive and most complex surveys on disability ever conducted. This chapter describes the background of the NHIS-D, its design and contents, its technical characteristics, and initial efforts to disseminate its findings. It provides a basic background on the NHIS-D for readers of this volume, and provides analysts working with the NHIS-D insight into some of the design and development issues that have not been previously described in public documents.

This article presents an application of survey non-response theory to a specific population with disabilities. From 1994 to 1997 the U.S. National Health Interview Survey (NHIS) did a special, two-phase study of disability. This survey format allowed for response patterns of the disabled population to be operationalized into contact, cooperation and proxy/assisted versus self-response categories. Using these data, the authors investigated the effects of severity of activity limitation at first interview on response patterns at second interview, with statistical controls for other characteristics related to the response outcome. The statistical results of the study show that respondents with moderate or severe activity limitation are more likely than those with mild activity limitation to be contacted and to cooperate, yielding higher response rates. However, respondents with a higher degree of activity limitation are also more likely to have proxy/assisted responses at re-interview. Barriers to self-response in household surveys are discussed in the concluding remarks.

The objective of this study is to show the utility of the newly-approved World Health Organization’s International Classification of Functioning, Disability, and Health (ICF) as a framework for organizing data from the National Health Interview Survey describing limitations in life activities among the U.S. population. Data were obtained from the 1994 to 1995 National Health Interview Survey (NHIS) Disability Supplement, Phase I (n=202,569). Forty-two items were selected from the survey to operationalize selected life domains of the ICF. Results indicated a prevalence rate of 19% for at least one life-domain limitation, with rates of limitations increasing with age, lower income and less education. Movement limitations were most frequently reported across the sample, but variations occurred within demographic characteristics. Life activities by sex and race produced noteworthy differences, by race/ethnicity generally, and by sex and race/ethnicity specifically. An example of mental health issues highlighted the use of the framework for health outcomes.

The ICF provides a foundational conceptual and classification system for improving disability science. These data suggest that the ICF has utility by providing data consistent with other disability measures, while providing an expanded and integrated model for science and policy. Fresh information is gleaned from organizing the data by ICF’s personal activity limitations. Differences by demographics across life domains, for example, can be more clearly presented and future analyses can assess associated impairments and environmental factors, including health service planning, health promotion, and access to care. The system can frame coherent integrated public health science and associated interventions to address the health and well being of people with disabilities.

Family health can be studied using the 1994–1995 National Health Interview Survey Disability Supplement by linking children to their mothers and other family members. However, the data item required to link is missing for 13% of children. We found that unlinked children and their probable mothers differed in many respects from their counterparts who could be linked, and exclusion of these mothers and their children from the analysis could bias results by introducing error due to incomplete coverage of the target population. We developed and validated a simple algorithm to match these children with their probable mother.

This paper examines barriers to work among adults with disabilities in two specific areas – searching for jobs and workplace accommodations – using data from the 1994/1995 National Health Interview Survey Disability Supplement. Focusing on a subgroup of “work-oriented” persons, the paper finds that difficulties in looking for work are widespread, encountered by more than half of our sample of non-workers with disabilities. While there are a variety of reasons people report for being discouraged in looking for work, lack of appropriate jobs, lack of information about appropriate jobs, and transportation problems are frequently cited. Those with lower levels of education, less previous work experience, and more severe activity limitations have the most difficulty searching for jobs. We also find that about one-third of our work-oriented non-working sample of adults with disabilities report needing workplace accommodations. The most common specific needs are special work site features such as accessible parking, transportation, elevators, and modified work stations. While a greater proportion of non-workers need more accommodations than workers, the types of accommodations most frequently needed are similar. We also find that even after controlling for severity of limitations and demographic characteristics, reporting a need for accommodation is still negatively correlated with the probability of working.

This study examined use of preventive health care services, for working-age adults with mobility limitations (uses mobility aids, has difficulty walking, difficulty standing for extended periods of time, or difficulty climbing steps) and for working-age adults reporting no mobility limitation, in order to identify similarities and disparities between the two populations. We analyzed data from the 1994 National Health Interview Survey Disability Supplement and NHIS Year 2000 file with cross-tabulation and logistic regression procedures to examine the relationship between mobility limitation and use of health screenings, immunizations, and health behavior counseling. Results were mixed, but disparities in preventive service use were identified.

Persons with disabilities can experience problems obtaining health care. Using the 1994–1995 National Health Interview Survey disability supplement, we examined health insurance coverage and access to health services for working-age adults with mobility problems (difficulty walking, climbing stairs, standing): 6.1% (estimated 9.48 million) of persons 18–64 years old. People reporting minor and moderate mobility difficulties had slightly lower health insurance rates than those without mobility problems (around 76% compared to almost 80%). People with mobility difficulties were more likely than others to be denied coverage and to cite pre-existing health conditions as the reason.

Access to health care, particularly for children, remains a topic of great importance to policy makers in the United States. Recent attention focuses primarily on the enactment and subsequent expansions of the Children’s Health Insurance Program (CHIP) (Kenney, Ullman & Weil, 2000). Though the legislation affects all qualifying low-income children, the unique service needs of children with disabilities justify a closer look at the relationship between health insurance, income, and needs amongst children with disabilities. This analysis seeks to answer the following questions. To what extent do children with disabilities need various supportive health services? Does this need vary across type of disability or income level? Do children with health insurance, either public or private, have fewer unmet needs than children without health insurance? Answers to these questions will assist policy makers when determining who should be targeted to receive additional assistance in the future as well as evaluate the effectiveness of current mechanisms in delivering supportive health services to children with disabilities.

We find the presence of a sibling with disability in a household is associated with greater risk of lower health status, unmet needs for routine medical care, and number of bed days due to sickness or injury. This is true both for children with or without disability. These relationships persist with controls for other aspects of the family environment that are associated with disability (socioeconomic status, family structure, and labor force participation). Having a co-resident sibling with disability rivals poverty, minority race or ethnic status, and one-parent households as a major risk factor for these negative child health outcomes.

The purpose of this study was to assess lifetime economic costs for people with four developmental disabilities (DDs): mental retardation, cerebral palsy, hearing loss, and vision impairment. Estimates were generated for direct medical costs, direct non-medical costs, and productivity losses resulting from increased morbidity and premature mortality. Findings suggest that lifetime costs, in excess of costs for individuals without DDs, are approximately $870,000 per person for mental retardation and $800,000 per person for cerebral palsy (in 2000 dollars). Analogous cost estimates for hearing loss and vision impairment are approximately $330,000 and $470,000, respectively. Roughly four-fifths of total costs reflect productivity losses.

This article describes the use of the National Health Interview Survey-Disability Supplement (NHIS-D) to estimate the prevalence and general characteristics of persons with intellectual and/or developmental disabilities in the non-institutionalized U.S. population. It provides estimates of the populations of non-institutionalized persons with intellectual disability (defined categorically), with developmental disabilities (defined functionally) and with both. It describes how the prevalence of intellectual and/or developmental disabilities varies by age, poverty status and other demographic variables. It describes how intellectual disabilities and developmental disabilities are operationally different, and how the people identified in those groups differ substantially both in number and in demographic characteristics. An analysis of poverty status among adults reveals that poverty is significantly more common for women, people who were not white, people with intellectual or developmental disabilities, adults with less than 12 years of education, and people living with a spouse or alone (as compared to people living with relatives such as parents or siblings).

Research on women’s health has increased substantially in the past decade, but this has not been paralleled in the area of developmental disabilities. In developmental disabilities research, there has been little attempt to disentangle the impact of age, intellectual disabilities, and other developmental disabilities on women’s health. The 1994–1995 Disability Supplement to the National Health Interview Survey, administered to a representative sample of the U.S. population, was used to describe the aging process in the community for women age 30 and older with mental retardation (MR), developmental disabilities (DD) or both (MR/DD). Definitions of MR and DD consistent with professional and legal standards were developed and adapted to the NHIS-D questions. Approximately 77 million civilian, non-institutionalized women in the United States were age 30 and older at the time of the survey. Among these women an estimated 0.56% have mental retardation or developmental disability. Compared with women in general, women with these disabilities were disproportionately absent in the community, had negative perceptions of their health status, and their health indicators tended to support these perceptions. Most women with these disabilities were independent in activities of daily living (ADL), but instrumental activities of daily living (IADLs) posed more of a challenge, and limitations in major activities were common. Limitations in mobility were common among women with DD.

We study disability duration and two aspects of disability timing (simultaneous vs. gradual onset; childhood vs. adulthood onset) for U.S. community-dwelling adults. The data set is the National Health Interview Survey Disability Supplement. Disabilities in personal care, household management, and physical tasks are analyzed. Results show that most adults with disability are older and have recent onsets. But up to a third of those whose disability started in childhood have entered middle and older ages. For most people, disabilities in a domain usually all start at the same time; gradual accumulation is less common. The mixing of simultaneous and gradual onsets, and of childhood-onset and adulthood-onset, produces great heterogeneity in the population of disabled adults. Our results give demographic support to the contemporary movement in local and state jurisdictions to combine aging services and disability services.

Now that the threat of infectious disease is under control among the Native American population, the prevalence of chronic disease and occupational illness has become the focus of concern, particularly in relation to associated mortality and morbidity. This analysis addresses the issue of disability as caused by chronic illness, accidents and occupational illness among native populations and provides prevalence estimates of disability as measured by functional and activity limitations. The analysis also provides a description of the socioeconomic situation among Native Americans with various impairments and limitations. Compared to whites, blacks and persons of other races, Native Americans report the highest levels of impairment and functional and activity limitations. Overall, 32% report some type of limitation. As for those of all other races, the rates of prevalence increase with age and are associated with low levels of education and income. However, the rates among the youngest age group of Native Americans are greater whether examining physical limitations or task/activity limitations. Logistic regression analysis indicates that when controlling for all the characteristics commonly associated with limitations and impairment, race continues to be a predictor of both physical and task/activity limitations, with Native Americans 29% more likely to report some form of limitation.

The National Health Interview Survey Supplement on Disability (NHIS-D) represents an extraordinary accomplishment to which many people have contributed. The breadth of items collected from a nationally representative sample of persons with disabilities, of all ages, enables us to undertake many analyses that were not previously possible. Several examples of recently conducted analyses that were stimulated by federal policies and programs are discussed. The paper presents suggestions for facilitating additional analyses. Strategies and options for collecting data on persons with disabilities in the future are also discussed.

Barbara M. Altman, a Sociologist with a Ph.D. from the University of Maryland, is currently a Special Assistant on Disability Statistics at the National Center for Health Statistics and an Adjunct Associate Professor at the University of Maryland, College Park. Her previous position was Senior Research Fellow with the Agency for Healthcare Research and Quality. She is a past president of the Society for Disability Studies and served on the founding Board of Directors of that organization. Her disability research interests focus in three areas: operationalization of disability definitions/measures in survey data; access to, financing and utilization of health care services by persons with disabilities, particularly working age persons and women with disabilities; and disability among minority groups. She is the author of a number of articles and book chapters on disability topics, and has served as editor of special issues of Disability Studies Quarterly and Journal of Disability Policy Studies. She is co-editor of this series Research in Social Science and Disability.Deborah J. Anderson, Ph.D., has conducted policy research in the area of Aging and Developmental Disabilities at the University of Minnesota since 1985. Her studies have included analyses of the health status, health conditions and health-related limitations and needs of older adults with mental retardation living in a variety of residential settings as well as in their own homes. These studies have included a longitudinal study of a 10% sample of older adults living in residential facilities licensed by developmental disabilities agencies, the National Nursing Home Survey of 1985, the National Medical Expenditure Survey of 1987, and the National Health Interview Disability Supplement (NHIS-D) of 1994–1995. She has also studied careproviders of older adults with mental retardation, innovative programs serving aging adults with developmental disabilities/mental retardation, and state agencies’ preparation for serving adults with mental retardation as they aged. Most of this research has been conducted as part of the NIDRR-funded RRTC on Aging and Developmental Disabilities. Dr. Anderson is also an Associate Professor in the Department of Psychology at St. Olaf College in Northfield, MN.Lynda L. Anderson, M.A., M.P.H., is a Resource Manager at No Place like Home in Robbinsdale, Minnesota. Ms. Anderson earned a Master of Arts degree in Human Service Administration and a Master of Public Health degree in Community Health. Ms. Anderson is a doctoral candidate in Work, Community and Family Education at the University of Minnesota. She has more than eighteen years of experience working with people with disabilities as a Direct Support Professional, Program Director, and Researcher. She has participated in NHIS-D analysis activities for the last five years.Sharon N. Barnartt, Ph.D., is Professor of Sociology at Gallaudet University. She has co-authored two books: Deaf President Now: The 1988 Revolution at Gallaudet University (1995) and Contentious Politics in the Disability and Deaf Communities (2001). She has also presented papers and published widely in the areas of socio-economic status and disability/deafness, legal and disability policy issues, and social movements in the deaf and disability communities. She is a former president of the Society for Disability Studies, co-editor of Research in Social Science and Disability and on the editorial board of Journal of Disability Policy Studies.Phillip W. Beatty, M.A., is a Senior Research Associate at the National Rehabilitation Hospital Center for Health & Disability Research in Washington, DC. His recent research focuses on predictors of access to health services among adults with disabilities. Mr. Beatty is also conducting research to determine the ways in which functional outcomes information is being used by stakeholders in the medical rehabilitation industry.Edward Brann, M.D., M.P.H., is Acting Director of the Division of Human Development and Disability, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention. The division conducts a number of research and program activities for people with disabilities.Hong Chen, M.S., is an Economist in RTI International’s Division of Health Economics Research. His work focuses primarily on the analysis of large claims and survey databases, with an emphasis on diabetes prevention, substance abuse, and competitive bidding for durable medical equipment.Lisa J. Colpe, Ph.D., M.P.H., is a Clinical Epidemiologist Specializing in Survey Design and Research. At the time the work on this chapter was done, she was an Epidemiology Training Program Fellow in the Division of Health Interview Statistics, National Center for Health Statistics.Roger B. Davis, Sc.D., is Associate Professor of Medicine at Harvard Medical School and Associate Professor of Biostatistics at the Harvard School of Public Health. Dr. Davis has overseen the statistical design of numerous clinical trials, especially involving cancer and AIDS therapies. An expert in survival analysis, he also participates in health services research and clinical epidemiology studies with colleagues at Beth Israel Deaconess Medical Center, where he serves as Biostatistician in the Division of General Medicine and Primary Care.John Drabek, is an Economist in Office of Disability, Aging, and Long-Term Care Policy in the U.S. Department of Health and Human Services. He received his B.A. in Economics from Northwestern University, and his Ph.D. in Economics from the University of California, Santa Barbara. Prior to joining the federal government, he performed research at the University of Southern California, and at the University of California, Los Angeles.Laura J. Dunlap, M.A., is a Health Economist in RTI International’s Center for Interdisciplinary Substance Abuse Research. Since joining RTI in 1994, she has worked on studies analyzing the costs and benefits of substance abuse treatment, the effect of treatment services on post-treatment outcomes, and the costs and cost-effectiveness of public health and treatment interventions aimed at special populations such as drug users and low-income women.Holly J. Fedeyko is a former employee of the Disability and Health Branch, CDC in Atlanta, Georgia. While at the CDC she focused her efforts on Research in disability issues as related to questions from the National Health Interview Survey. She received her M.P.H. in Epidemiology and Environmental Health from Emory and her B.S. in Biology from McGill. She is currently employed as an analytical consultant for a private company and now resides in the San Francisco Bay area.Frances K. Goldscheider, University Professor and Professor of Sociology, began her Brown career in 1974. Since obtaining her Ph.D. in Demography from the University of Pennsylvania in 1971, Goldscheider has focused her research on census and survey data to address questions related to family structure and coresidential relationships, examining causes and consequences of change. Goldscheider pioneered research on the single-person household, and on home leaving and return to the nest of young adults, and has examined issues of labor force and family decisions of 20th century American women. She is an expert on family structure and relationships, fertility, parenthood, household economy, and marriage. Her intergenerational focus (on the living arrangements of young adults and the elderly) has expanded to include gender issues, particularly marriage and divorce, with a strong concern with the consequences of family structure for investments in childhood and young adulthood. Recent research interests include men’s roles in parenting and in the family.Scott D. Grosse, Ph.D., is a Health Economist at the National Center for Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention. He conducts applied research on the costs associated with various childhood conditions and economic evaluations of screening programs and interventions intended to improve health and developmental outcomes in children.Gerry E. Hendershot, Ph.D., is a Consultant on Disability and Health Statistics. From 1985 to 2001, he held various positions on the staff of the National Health Interview Survey, including Assistant to the Director for Data Analysis and Dissemination. He had a lead role in promoting, designing, and analyzing the National Health Interview Survey on Disability. He is the author of many published statistical reports on disability and other health-related topics.Dennis P. Hogan, Professor of Sociology, joined the Population Studies and Training Center at Brown University in 1995. He received a Ph.D. in Sociology from the University of Wisconsin-Madison in 1976. He has taught at both the University of Chicago, where he acted as associate director of the Population Research Center, and Pennsylvania State University, where he served as director of the Population Research Institute. In 1997, Hogan was named to an endowed professorship as the Robert E. Turner Distinguished Professor of Population Studies. Some of his research interests include the interrelationships of the family lives of individuals and their social environments, the measurement of disability, family consequences of disability, and the transition to adulthood. Hogan’s current research focuses on child disability. He is the principal investigator on grants supporting this program from the National Institute for Child Health and Human Development, the National Center for Medical Rehabilitation Research, the Assistant Secretary for Planning and Evaluation, the Federal Interagency Forum on Child and Family Statistics Subcommittee on Disability and the Spencer Foundation.Ghada al Homsi, M.S., is an Economist in RTI International’s Center for Interdisciplinary Substance Abuse Research. Her work focuses on the analysis of large surveys and the design and maintenance of databases of program costs.Amanda A. Honeycutt, Ph.D., is an Economist in RTI International’s Division of Health Economics Research. Since joining RTI in 1998, she has led a number of studies on the cost-of-illness, the cost of intervention programs, and the cost-effectiveness of prevention and treatment interventions that focus primarily on diabetes, HIV/AIDS prevention, and children’s health, disability, and development.Peter C. Hunt, M.P.H., was an Association of Schools of Public Health Fellow in the Division of Health Interview Statistics, National Center for Health Statistics, at the time work on this chapter was done. He subsequently served as a Special Assistant to the Director of the National Institute of Disability and Rehabilitation Research. He is currently a Research Associate at the University of Pittsburgh Model Center on Spinal Cord Injury.Lisa I. Iezzoni, M.D., M.Sc., is Professor of Medicine at Harvard Medical School and Co-Director of Research in the Division of General Medicine and Primary Care, Department of Medicine, at Beth Israel Deaconess Medical Center in Boston. Her primary research interest is risk adjustment for assessing health care quality and improving the fairness of payments. A 1996 recipient of The Robert Wood Johnson Foundation Investigator Award in Health Policy Research, she also studies health policy issues relating to mobility impairments. Dr. Iezzoni is a member of the Institute of Medicine.Gwyn C. Jones, Ph.D., M.S.W., M.Ed., is a Senior Research Associate at the National Rehabilitation Hospital Center for Health & Disability Research in Washington, DC. She is a former ATPM/CDC Fellow and current grantee. Her research and publications have focused on health risks, chronic conditions, and use of preventive services among working-age adults with disabilities, prescription drug use among non-elderly adults with disabilities, and rural Medicaid managed care for adults with disabilities.Judith D. Kasper, Ph.D., is a Professor in the Department of Health Policy and Management, and a Senior Research Associate in the Center for Health Services Research, at The Johns Hopkins Bloomberg School of Public Health. Her research interests include health policy in long-term care, aging and disability, access to health care for vulnerable populations, and the development and application of data sources for health policy and health services research. Dr. Kasper holds a Ph.D. in sociology from the University of Chicago.K. Charlie Lakin, Ph.D., is the Director of the Research and Training Center on Community Living at the University of Minnesota. Mr. Lakin has had extensive experience in gathering, analyzing, and using statistics from many primary and secondary data sources with the products of this work included in more than 200 publications in developmental disabilities and related services. Mr. Lakin was a member of the six-person external technical advisory panel on the instrumentation for the Disability Supplement. Mr. Lakin serves as Associate Editor of Mental Retardation, and consulting editor of The Journal of the Association for Persons with Severe Handicaps (JASH), the Journal on Intellectual and Developmental Disability and Social Science and Disability.Sheryl A. Larson, Ph.D., is a Research Associate at the Research and Training Center on Community Living at the University of Minnesota. She earned her Ph.D. in Educational Psychology from the University of Minnesota. She has 20 years of experience in services to persons with DD as a residential counselor, behavior analyst, social worker, and program evaluator and has worked for the RTC for the last 14 years. Ms. Larson was the Co-Principal Investigator for a two-year NIDRR Field Initiated Project which used the National Health Interview Survey Disability Supplement to examine the characteristics and service needs of persons with intellectual or developmental disabilities. She directed a supplement to the Research and Training Center on Community Living’s core grant that funded an international user’s conference in June 2000 for researchers analyzing NHIS-D topics. She has co-authored several papers using NHIS-D data. Dr. Larson has also co-authored several books, book chapters, journal articles and technical reports on workforce development issues, residential services, and community integration for persons with developmental disabilities and is a consulting editor of Mental Retardation.Donald J. Lollar, Ed.D., Senior Research Scientist, Division for Human Development and Disability, National Center on Birth Defects and Developmental Disabilities at the Centers for Disease Control and Prevention in Atlanta. His advanced degrees are from Indiana University, and his most recent writings include co-editing an Archives of Physical Medicine and Rehabilitation supplement on the Science of Disability Outcomes, and articles for the 2003 Annual Review of Public Health and 2002 Public Health Reports outlining public health strategies to improve the health and well-being of people with disabilities. He has spent the past seven years developing public health science and programs to improve the health of people with disabilities, prevent secondary conditions, and increase participation in society. He currently serves as the co-lead of the Healthy People 2010 workgroup on Disability and Secondary Conditions (Chap. 6 of HP 2010). Dr. Lollar began involvement with the WHO classification ICIDH in 1994 while still in private practice, assessing potential utility of ICIDH-2 for clinical records. He is currently a part of the team to adapt the ICF to improve its utility for children and youth.Pamela Loprest is a Labor Economist and Senior Research Associate at the Urban Institute. Her research focuses on low-wage labor markets and how government policies can help to reduce and remove barriers to work among disadvantaged populations. Dr. Loprest has a Ph.D. in Economics from the Massachusetts Institute of Technology and has been at the Urban Institute since 1991.Elaine Maag is a Research Associate in the Urban Institute’s Income and Benefits Policy Center. Her research focuses on policies affecting youth with disabilities and employment opportunities for adults. She also conducts research on how tax policy affects low-income families. Ms. Maag holds an M.S. in Public Policy from the University of Rochester.Jennifer M. Park is a Post-Doctoral Fellow at the Harvard Graduate School of Education. Her current research is funded by a grant she holds from the American Education Research Association to examine cognitive development among first grade youth with and without emotional impairment. Her dissertation explored cognitive growth among kindergarteners with and without perceptual impairment. Dr. Park holds a Ph.D. in Sociology from Brown University, where her research examined the diverse effects of child disability on family outcomes.Elizabeth K. Rasch, M.S., P.T., is an Associate Service Fellow at the National Center for Health Statistics, CDC, working in the area of disability statistics. She is a Ph.D. candidate at the University of Maryland, Department of Physical Therapy and Rehabilitation Science, with a concentration in Epidemiology. Her research interests include the health of persons with disabilities, factors that contribute to disability, as well as the use of and access to healthcare services by persons with disabilities. She has been actively involved in research since 1985 and has published articles and book chapters on topics related to disability and rehabilitation.Anne W. Riley, is an Associate Professor in the Department of Health Policy and Management, in the division of Health Services Research, at the Johns Hopkins Bloomberg School of Public Health. Dr. Riley has expertise in the assessment of mental health and health, especially of children and adolescents, methods development, and evaluation systems for monitoring the outcomes of care for youth.Diana E. Schendel, Ph.D., is a Lead Health Scientist at the National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention. She directs both intramural and extramural epidemiologic studies of reproductive and developmental outcomes, with a primary focus on cerebral palsy, autism, and other neurodevelopmental problems.Hilary Siebens, M.D., is Lecturer in the Department of Physical Medicine and Rehabilitation (PMR) at Harvard Medical School and Associate Director, PMR Service, at the Massachusetts General Hospital. She received clinical training in internal medicine, geriatrics, and PMR. Her publications address exercise among older adults, models of rehabilitation, and quality improvement initiatives.Lois M. Verbrugge, Ph.D., M.P.H., is Distinguished Senior Research Scientist in the Institute of Gerontology at the University of Michigan. She has contributed to disability theory and has conducted analyses of arthritis disability, gender differences in morbidity and mortality, and co-morbidity, using large-scale data sets. Her recent publications have emphasized the relative benefits of equipment and personal assistance for disability, the interleaving of aging and disability, and global indicators of disability. She was awarded the American Psychological Association Distinguished Contribution to Women’s Health Award in 1994.Whitney P. Witt, Ph.D., M.P.H., is an Assistant Professor of Medicine in the Division of General Internal Medicine and Center for Healthcare Studies at the Northwestern University, Feinberg School of Medicine. Dr. Witt’s prior work focuses predominately on people living with HIV/AIDS, including children and their families. Over the last five years, she has applied her experience in advocacy, policy, and research on vulnerable and high-cost, chronically ill populations to the field of maternal and child health services research. Dr. Witt’s research emphasizes the importance of family adaptation in ensuring the mental health of children with disabilities and for helping these children obtain access to mental health services. Most recently, her work has focused on the impact of maternal depression on familial health and mental health, preventive care practices, and use of health and mental healthcare services. She holds a Ph.D. in health services research and a M.P.H. from the Johns Hopkins Bloomberg School of Public Health and a B.A. in women’s studies and law from Hampshire College.Li-shou Yang, Ph.D., is Research Investigator in the Institute for Social Research at the University of Michigan. Trained in social demography, her research focuses on the family, the life course, and social change.