Disability: Neurocognitive Disabilities
- Lisa S. PatchnerLisa S. PatchnerDepartment of Social Work, Ball State University
- and Kevin L. DeWeaverKevin L. DeWeaverUniversity of Georgia
The multiplicity of disability definitions can be attributed to the heterogeneity of disability, its multifactoral nature, and its effects across the life span. Of particular concern to the social work profession are those persons with neurocognitive disabilities. Neurocognitive disabilities are ones where a problem with the brain or neural pathways causes a condition (or conditions) that impairs learning or mental/physical functioning or both. Some examples are intellectual disabilities, autism spectrum disorders, and savant syndrome. Neurocognitive disabilities are the most difficult to diagnose often times because of their invisibility. Providing services for people with neurocognitive disabilities is very difficult, and people with these disabilities are among the most vulnerable populations in today's society. This entry discusses neurocognitive disabilities and current and future trends in social work disability practice.
- neurocognitive disability
- cognitive disability
- neurological disability
- disability rights
- quality of adjusted life year measurements
- person-centered planning
- constructionist approach to disability
- consumer-driven service delivery
- International Classification of Functioning, Disability and Health
- disability demographics
Since the mid-1970s, the area of disability practice has evolved more rapidly than any other social work practice area (Mackelprang, 2002; Patchner, 2005; Redfoot, 2003). This evolution can be explained by the rapid growth of scientific discovery, our understanding of the human body and how it works, and the disability rights movement. Medical and technological advances, civil rights, and sociopolitical changes within society have challenged social work practitioners to be current and relevant within the field of disability practice. Historically, social workers have usually followed a medical or rehabilitative model of practice which has resulted in a discriminatory and biased approach to disability practice (Mackelprang, 2002; Patchner, 2005). Our lack of an enlightened model of practice that does not locate the problem strictly within the person with a disability has led to an increase in other personnel, for example, rehabilitation workers and paraprofessionals, working within the disability practice arena. Subsequently, there exists no standardized model of disability practice within the profession of social work (Gilson & DePoy, 2002). When addressing the entire specialty of disability practice, especially cognitive disabilities, social work practitioners must take into account this evolving landscape.
The multiplicity of disability definitions and terms can be attributed to the heterogeneity of disability, the multifactoral nature (that is, many contributing factors), including causal factors, of disabilities, and the effects of disabilities across the life span on the individual, family, and society. Words such as neurodevelopmental, developmental delay, cognitive delay, learning disabilities, sensory integration dysfunction, physically challenged, sensory impairment, morbidity, chronic illness, and a host of other terms all fit within the larger scope of neurological or cognitive disabilities. These terms are beginning to be used in some service organizations to let people know who they serve. One example of this is the Orion Academy: A Unique School for Neurocognitive Disorders (http://www.orionacademy.org) in Moraga, California.
Being diagnosed or called a person with a disability does not make the individual a person with a disability. Disability today takes on another paradigm, that of functionality within the workforce and broader society (DeWeaver, 1995; Patchner, 2005). For example, a person with cerebral palsy carries a diagnostic label but may not consider himself or herself a person with a disability because the individual is not limited in any major life activity such as work. A deaf person from birth most likely would reject the disability label altogether. Social workers should be familiar with how disability definitions can discriminate and prevent persons from receiving needed health and welfare services.
Some contemporary definitions of disability are as follows:
Americans with Disabilities Act (1990). An individual with a disability is defined as a person who
has a physical or mental impairment that substantially limits a major life activity, or
has a record of such an impairment, or
is regarded as having such an impairment.
Social Security Administration (2007). Disability under Social Security is based on the inability to work. Under Social Security rules if individuals cannot do work that they did before, and if they cannot adjust to other work because of their medical condition(s), they are considered disabled.
The disability must also last or be expected to last for at least 1 year or to result in death.
International Classification of Functioning, Disability, and Health (2001). Disability serves as an umbrella term for impairments, activity limitations, or participation restrictions of the individual.
The Developmental Disabilities Assistance and Bill of Rights Act (1990). Developmental disability means a severe, chronic disability of a person 5 years of age or older that
is attributable to a mental or physical impairment or a combination of both;
is manifested before the person attains 22 years of age;
is likely to continue indefinitely;
results in substantial functional limitations in three or more of the following areas of major life activity: self-care, receptive and expressive language, learning, mobility, self-direction, capacity for independent living, and economic self-sufficiency;
reflects the person's need for a combination and sequence of special, interdisciplinary, or generic care, treatment, or other services that are lifelong or of extended duration and are individually planned and coordinated; except that such term, when applied to infants and young children, means individuals from birth to age 5, inclusive, who have substantial developmental delay or specific congenital or acquired conditions with a high probability of resulting in developmental disabilities if services are not provided.
The United Nations Convention on the Rights of Persons with Disabilities (2007). Disability is an evolving concept and that disability results from the interaction between persons with impairments and attitudinal and environmental barriers that hinder their full and effective participation in society on an equal basis with others.
Most disabilities have a neurological component, either by genetics (genes, chromosomes, metabolic) or by injury (accidents, disease, poisoning). Cognitive disability pertains to the mental capacity in orientation (time, place, person), intellect, psychological, memory, sensory integration, and thought process. Routinely, professionals have utilized standardized measures of intelligence or IQ range to classify the level of cognitive deficits, especially with people with intellectual disabilities (formerly called mental retardation) (Sulkes, 2003). Such classifications of intelligence were viewed as difficult to apply meaningfully, restrictive (Slick, Sherman, & Iverson, 1999), and discriminatory by many in the disability community and can exacerbate the stigma of cognitive disability (Corrigan, 2007). One of the reasons that the term mental retardation was dropped was to get away from the stigma of the term and its inappropriate shortcuts and slang, for example, “retarded,” “retards,” and “tard.” Currently, the International Classification of Functioning, Disability and Health classifies cognitive deficits by global mental functions along a dimensional continuum. These mental functions include consciousness, orientation, intelligence, psychosocial, temperament and personality, energy and drive, and sleep functions (World Health Organization, 2001).
The vast majority of persons with disabilities do not have cognitive disabilities. Therefore, in this entry, the term neurocognitive disabilities refers to persons who have both a neurological disability as well as a cognitive disability. This may include (but is not limited to) the disabilities of autism, down syndrome, Fragile X, intellectual disability, developmental disabilities, learning disabilities, Williams syndrome, Alzheimer's disease, savant syndrome (formerly idiot savant), and sensory integration dysfunction. Persons with neurocognitive disabilities are the most vulnerable population in the United States because of their unique needs in care, self-determination, and self-advocacy (DeWeaver, 1995; Patchner, 2005). Most residents of institutions for people with disabilities are persons with neurocognitive disabilities, many of whom have behavioral challenges to overcome before they can successfully integrate in the community. Most civil rights advances that have assisted persons with disabilities have been less successful in advancing the quality of life for those with cognitive deficits (National Association of Social Workers, 2003b).
According to the U.S. Census Bureau's (2006) report Americans with Disabilities: 2002, data collected from the Survey of Income and Program Participation show that over 51.2 million (18.1%) Americans have a disability, of which 32.5 million (11.5%) have a severe disability. The Census Bureau also notes that more than half of those aged 21–64 had a job, more than 4 of 10 between the ages 15 and 64 used a computer at home, and a quarter of those between the ages 25 and 64 had a college degree. The Census Bureau delineates between severe disabilities and other disabilities and collects data on mental disabilities for specific age groups. These data indicate that over 14 million, or 6.4%, of Americans aged 15 years and older have some form of mental disability. Since the U.S. Census figures on severe disability include those who have severe physical disabilities with no cognitive impairment, it is not an accurate measure of those individuals who possess both neurological and cognitive disabilities.
The National Organization on Disability (2004) commissioned the Harris Survey of Americans with Disabilities: 2004 and found that 54 million Americans had one or more disabilities. This report also indicates that Americans with disabilities are at significant disadvantage when compared with other Americans on 10 indicators. Since 1986, The Harris Survey has indicated slow progress in improvement of these indicators. Some significant findings are as follows: 18% go without adequate health care; only 35% of persons with disabilities are employed, and 22% of them report discrimination; persons with disabilities are 3 times more likely to live in poverty; twice as likely to drop out of high school; twice as likely to have problems with transportation; 22% of those employed report job discrimination; and, the severity of disability significantly increases disadvantages in all areas of life (National Organization on Disability, 2004).
Owing to population identification and sampling variability, these reports can be expected to show different outcomes. However, both surveys show significant economic and life disadvantages for those with severe disabilities, which would include those having neurocognitive disabilities. This would suggest a disparity in health care and social supports for the most vulnerable population in the United States.
Of particular concern in the United States is the growing numbers of children diagnosed with the neurocognitive disability of autism spectrum disorders (ASDs). The U.S. Centers for Disease Control recently published a report on the prevalence of ASDs (Rice, 2007). These data, collected from 14 states, showed an increase in ASDs from 1 in 166 in 2000 to 1 in 150 children in 2002. Of particular concern was the finding that 1 in 104 male children are diagnosed with an ASD. Furthermore, a child is diagnosed with autism every 20 minutes, and the number of cases has increased 15-fold since 1991 (Autism Speaks, 2007; Graziano, 2002). That year, companies began putting thimerosal, a mercury-based preservative, into vaccines given to very young children. This practice has since stopped; however; many infants and young children were exposed to thimerosal. Young children now are vaccinated 23 times before they reach age 5. Scientific and political battles are now being fought over whether there is a connection between thimerosal and autism. A recent government-funded clinical study indicated that thimerosal did not increase autism numbers. Most recently, the common flu shot given to pregnant women has come under scrutiny. Obviously, many questions remain unanswered. Still others question whether sun block may be blamed for autism. As sun light assists in producing Vitamin D, sun block can inhibit its production. It is hypothesized that the interference in Vitamin D production could be related to autism increases (see vitamindcouncil.com). Curiously enough, the Amish, who do not get vaccinations, flu shots, or use sun block, are not afflicted by autism. Social workers must follow research in this area to disseminate to their clients and community.
The World Health Report: 2006 calculates both life expectancy at birth and healthy life expectancy at birth. This is in recognition that disability will encompass a portion of the life span of people around the world. The report shows that in the United States, life expectancy at birth for males is 75.0 and for females is 80.0, whereas, healthy life expectancy for males is 67.2 and for females is 71.3 (World Health Organization, 2006). Most of us can expect disability to occur during some time in our lives, and for the majority of us this will occur during our later years (National Association of Social Workers, 2003a).
Many persons with cognitive disabilities are hidden and may escape official counts on the number of people in the population with disabilities. Several reasons for this could be discrimination toward underserved populations, lack of information that could mean less funding for governmental programs, restrictive and changing definitions on developmental disability, and persons and families who do not wish to identify the person as having a disability. Social workers engaged in policy practice need accurate demographic data in order to clearly represent the number needing health, social, and public assistance services.
Theory, Research, and Best Practices
Historically, in the area of disability practice, the social work knowledge base has relied on theoretical applications such as behaviorism, anatomical knowledge, and, later, the human genome project that stemmed from scientific discovery and medicine (Patchner, 2005). Because of recent advances in science and medicine, persons with disabilities have greater longevity and a better quality of life. Undeniably, these advances in science and medicine have resulted in social work practice that was medically modeled. As social service delivery systems matured, social work practice moved its focus from the medical model to social service delivery and rehabilitation model. Until recently, this left little room for self-determination of the person and family. During the 1970s and 1980s, with the arrival of the independent living movement and civil rights advocacy and legislation, social work disability practice began to focus on the self-determination of the person and a constructionist approach to disability began to emerge (Asch, 2001). This approach to disability views the interaction between persons with disabilities and society as dysfunctional. The approach proposes that it is society's responsibility to fix itself and not the person (Gilson & DePoy, 2002). The social work profession grapples with both medical progress in identifying and treating disabilities and advocating for a society, through ongoing progressive change, that respects the self-determination of the person. Most grapple with this situation by performing the main functions of social work: helping the person with a disability and their family via direct services and using advocacy to attempt to change policy for this vulnerable group of people. Many cases are complex, and the social worker has to remain flexible and prioritize needs, which often are clinical first and then policy-changing (see the Pediatric Case Example that follows).
Pediatric Case Example
Lee Chin is a 2-year-old child with dual diagnoses of dwarfism and Down syndrome. He requires a trach and continuous oxygen, and exhibits feeding problems because of difficulty in swallowing. At risk for increased respiratory infections due to the trach, Lee Chin has required numerous hospitalizations. The child sits with the support of a brace, exhibits better use of his upper extremities, is alert but severely developmentally delayed. Family and professional staff have observed Lee Chin's attempt at speech and minimal use of upper extremities. The child is currently being treated at a rehabilitation center, following his most recent hospitalization.
Lee Chin lives with his parents and 3-year-old brother. There had been reported domestic stress between the parents, which resulted in the father disengaging from any caretaker functions of the child. The family emigrated from Vietnam 2 years ago, and has experienced the additional stress of cultural assimilation. There exists no extended family support system and limited ethnic community support. The family has experienced several significant losses during the past several years—their son's serious medical problems, strained relationship between the parents, cultural identification, and lack of familial network.
Several community- and medical-based agencies are providing services in the home where Lee Chin receives ongoing medical care. These services include physical therapy, skilled nursing, medical social work services, and early education intervention. Some service providers have exacerbated family stress by the lack of cultural sensitivity to the unique needs of this newly immigrant family. Owing to possible cultural and language barriers, service providers did not encourage the self-determination of this family in making informed treatment decisions regarding their son. As a result, Lee Chin's mother is uneasy in utilizing service providers, and retreats from available help when she feels threatened, misunderstood, or pressured into making a decision. An initial hospital multidisciplinary team evaluation of Lee Chin was discontinued when the mother exhibited fear and anxiety regarding the nature of the evaluation process. In addition, a communication breakdown, over a difference in treatment goals, between the treating physician and Lee Chin's mother has further complicated the treatment plan for the child. An interdisciplinary team, which included a health insurance case manager, was created. The interdisciplinary team evaluation focusing on feeding, speech/augmentative communication, cognitive issues, and future discharge planning was held at the rehabilitation facility where Lee Chin has been a patient for the past 2 weeks.
Chaired by the rehabilitation center social worker, the interdisciplinary team identified the complex psychosocial needs of Lee Chin and his family. They supported and partnered with the family during the decision-making process. Specifically, the mother was given flexibility in scheduling the skilled nursing services for her child in order to facilitate her work schedule outside the home, and to maximize her time with the home health nurse while enhancing her caregiver role. Discharge planning goals were to provide the medically necessary amount of skilled home health nursing home-based medical and community-based services, and parental decision making. The social worker used a family-centered approach to facilitate parental decision making regarding the future care of Lee Chin.
Theory and Research
A dichotomy has evolved where disability practice relies on both scientific advances for best practice knowledge, as well as sociopolitical standards which support the person in determining what best practice is. There exists a constant struggle to balance scientific and medical advances by supplying this research knowledge to persons with disabilities and their families so that they can determine what is useful for them (Patchner, 2005; Redfoot, 2003; Rose & Moore, 1995).
Perhaps the greatest scientific advances have occurred during the 13-year period from 1990 to 2003 of the International Human Genome Sequencing Consortium. During its initial efforts the entire DNA code for 30,000 human genes was mapped and sequenced. The functions of half of the discovered genes is now known, and researchers are continuing their effort in discovering all gene functioning. Some neurological conditions that have been identified in recent years include white matter diseases of the brain, cystic fibrosis, Huntington's disease, early-onset Alzheimer's disease, and progeria, which is a fatal rare condition characterized by advanced aging in young children usually by 2 years (see http://www.progeriaresearch.org). Once genes are identified, researchers hope to develop treatments to lesson the disease effects and progression or to directly treat damaged genes. It is hoped that in the future, many neurocognitive disabilities will not only be identified by their gene mutations but will be amenable to effective medical intervention (National Institutes of Health, 2006).
Identifying the Human Genome has raised many societal concerns regarding how genetic information will be used in the future. Some of these concerns deal with the ethical use of the information and the possibility that persons with such gene defects will be discriminated against and stigmatized (National Institutes of Health, 2006). To prevent misuse of genetic information, NASW (the National Association of Social Workers) and other organizations have supported the proposed Genetic Information Nondiscrimination Act (Pace, 2007). This act has received steady support from members of Congress and is expected to become law. Of additional concern is how gene identification will be utilized in calculating Quality of Adjusted Life Year measurements to determine through microeconomic models person-years lived by health status. Such estimates are used in cost-effectiveness analyses to determine the quality of life given a person's health status against medical treatment options. Such measurements could adversely affect those with neurocognitive disabilities in the area of cost control and rationing of health care (Patchner, 2005).
Social workers have a key role to play in the lives of persons with disabilities and their families. From direct practice to policy advocacy, the array of opportunities for social workers in disability practice continues to broaden as many live longer with chronic disabilities. No longer is disability viewed as a state experienced by a small percentage of our population. Intellectual disability alone can account for nearly 3% of the U.S.'s population (U.S. Census Bureau, 2006).
Best practice dictates an active involvement of the person with the disability and their family in all life area decisions. The economic term consumer-driven service delivery indicates a shift from a previous supplier-driven model to a demander-driven model. Persons with disabilities are the demander of services and, therefore, are the catalyst for what goods and services they desire and need. The professionals are the suppliers of services and they no longer direct the care and services that are to be provided, but are the facilitator in making sure that the person gets the care and services that they desire and need.
When an individual has a neurocognitive disability, the family or a close friend is instrumental in determining what the person's needs are and in finalizing services with professionals. The use of person-centered planning in working with persons with cognitive impairments and their family or friends has been extremely successful both in Canada (where it was developed) and in the United States (O'Brien & O'Brien, 2000). When employing this technique, the person and those close to the person outline together what is an optimal quality of life for the person. It begins by identifying the individual's hopes and aspirations and continues with an action plan to realize these goals. The person-centered planning process involves modifying goals, aspirations, and action plans until an optimal quality of life is achieved for the person (Patchner, 2005).
Best practices for professional social workers who work with persons who have neurocognitive disabilities involve a thorough understanding of consumer-driven strategies. These strategies may utilize person-centered planning and other consumer-driven modalities.
Policy practice is the responsibility of all social workers. Within the disability specialization, professional social workers partner with or represent the interests of persons and families who request assistance in advocating for policy change. Such activities may include advocating on the local, state, or federal levels for changes in fiscal allocations and services, speaking with legislators or bureaucrats, gathering data for policy analyses, and performing such analyses, or helping a person navigate the complex service delivery system. The most effective policy practice activities involve consumer advocates who, because of their own experiences, are most knowledgeable about gaps in services and unmet needs or solutions.
When it comes to best practices, the person and/or family are usually the “experts.” It is the social worker's responsibility to identify needs, assist in procuring services, navigate the maze of services, and promote policies and services to better serve this population.
Future Trends and Practice Implications
Future trends in practice will be affected by cost containment as well as quality of care concerns. According to Rose and Moore (1995), cost containment (provider-driven) and quality of care (consumer-driven) cannot exist together with a quality outcome as an expectation. Institutions, government, and social services have attempted to balance both concerns to please both constituent groups. A constant tension will exist unless policy makers successfully mediate between both forces (Redfoot, 2003).
New problems for people with neurocognitive disabilities will develop, and social workers will often assist with these new challenges. For example, as more people with intellectual disabilities live to an older age, who will provide for them as their parents either die or are unable to care for their offspring anymore? Formerly they were institutionalized; however, these facilities are being closed, partly to save state funds but primarily because of the lack of care and dignity accorded to persons with disabilities. Social workers can assist by identifying community-based housing and employment, and where appropriate find them guardians as well. Social workers can also alert their legislators that additional funding and adequate housing are needed for this.
Future practice trends will involve the modification of current practices such as interdisciplinary practice, restorative care, and holistic care to embrace disabilities across the life span. New specializations will develop in order to serve a greater heterogeneous population. The continuum of care will become more identifiable as private and public agencies may become more specialized. Technology innovations will allow persons with disabilities more self-determination and freedom of expression. And as society becomes more enlightened, we can expect that universal design (that is, accessibility in all areas of life for every person) will become commonplace (Kurtz, Dowrick, Levy, & Batshaw, 1996; National Association of Social Workers, 2003b).
Newer emerging trends will be controversial and will require vigilance by professionals. There will be a growing number of privatized services and less public services. Subsequently, because of cost containment priorities, we can expect a greater use of quality of adjusted life years in determining who gets what care and services. As cost containment becomes a pressing issue for government and industry, rationing of health and welfare services will become common. Macroutilitarian approaches to providing care will spar with microegalitarian approaches. The most vulnerable population at risk will be those with neurocognitive disabilities, who can be considered costly by society's standards (Maramaldi, Berkman, & Barusch, 2005; Patchner, 2005; Sacristan, 2003).
Social Work Practice Implications
There will continue to be a steep educational learning curve for professional social workers engaged in neurocognitive disability practice. Medical and scientific advances will require intensive continuing education. Letting go of the reigns and encouraging persons to develop and implement their own plan of care takes experience, acceptance of a new practice model, and maturity. Being knowledgeable about privatization of services in order to advocate and navigate for health and welfare services, housing, and employment will become an essential skill.
Persons with neurocognitive disabilities could easily fall through the cracks. Professional social workers who are knowledgeable about the evolving service environment are obliged to partner with this population to ensure dignity and the ability to earn a livelihood both today and in years to come.
- Asch, A. (2001). Critical race theory, feminism, and disability: Reflections on social justice and personal identity. Ohio State Law Journal, 62, 1–17.
- Autism Speaks. (2007). http://www.autismspeaks.org
- Corrigan, P. W. (2007). How clinical diagnosis might exacerbate the stigma of mental illness. Social Work, 52, 31–40.
- DeWeaver, K. L. (1995). Developmental disabilities: Definitions and policies. In R. L. Edwards et al. (Eds.), The encyclopedia of social work (19th ed., Vol. 1, pp. 712–720). Washington, DC: NASW Press.
- Gilson, S., & DePoy, E. (2002). Theoretical approaches to disability content in social work education. Journal of Social Work Education, 38, 153–165.
- Graziano, A. M. (2002). Developmental disabilities: Introduction to a diverse field. Boston: Allyn and Bacon.
- Kurtz, L., Dowrick, P., Levy, S., & Batshaw, M. (Eds.). (1996). Handbook of developmental disabilities: Resources for interdisciplinary care. Gaithersburg, MD: Aspen.
- Mackelprang, R. W. (2002). Social work practice with persons of disability. In S. F. Gilson et al. (Eds.), Integrating disability content in social work education: A curriculum resource (pp. 9–14). Alexandria, VA: Council on Social Work Education.
- Maramaldi, P., Berkman, B., & Barusch, A. (2005). Assessment and the ubiquity of culture: Threats to validity in measures of health-related quality of life. Health and Social Work, 30, 27–36.
- National Association of Social Workers. (2003a). Disabilities. Washington, DC: NASW Press.
- National Association of Social Workers. (2003b). People with disabilities. In P. L. Delo et al. (Eds.), Social work speaks (6th ed., pp. 270–275). Washington, DC: NASW Press.
- National Organization on Disability. (2004). Harris survey of Americans with disabilities: 2004. Washington, DC: Author.
- National Institutes of Health. (2006). History of the human genome project. Atlanta, GA: U.S. Centers for Disease Control.
- O'Brien, C. L., & O'Brien, J. (2000). The origins of person centered planning: A community of practice experience. Syracuse, NY: Center on Human Policy, Syracuse University.
- Pace, P. R. (2007). Mental health parity, Genetics bills backed. NASW News, 52, p. 1.
- Patchner, L. (2005). Social work practice and people with disabilities: Our future selves. Advances in Social Work, 6, 109–120.
- Redfoot, D. (2003). The changing consumer: The social context of culture change in long-term care. Journal of Social Work in Long-Term Care, 2, 95–110.
- Rice, C. (2007). Prevalence of autism disorders: Autism and developmental disabilities monitoring network, 14 sites, United States, 2002. Morbidity and Mortality Weekly Report, 56, 12–28.
- Rose, S. M., & Moore, V. L. (1995). Case management. In R. L. Edwards et al. (Eds.), The encyclopedia of social work (19th ed., Vol. 1, pp. 335–340). Washington, DC: NASW Press.
- Sacristan, P. (2003). Problems and solutions in calculating quality-adjusted life years (QALYs). Health Quality Life Ourcomes, 1, 80.
- Slick, D. J., Sherman, E. M., & Iverson, G. L. (1999). Diagnostic criteria for malingered neurocognitive dysfunction: Proposed standards for clinical practice and research. The Clinical Neuropsychologist, 13, 545–561.
- Sulkes, S. B. (2003). Mental retardation. In M. H. Beers et al. (Eds.), The Merck manual of medical information (2nd home ed., pp. 1626–1629). Whitehouse Station, NJ: Merck Research Laboratories.
- United Nations. (2007). The convention on the rights of persons with disabilities. New York, NY: Department of Economic and Social Affairs, United Nations.
- U.S. Census Bureau. (2006). Americans with disabilities: 2002. Washington, DC: U.S. Government Printing Office.
- World Health Organization. (2001). International classification of functioning, disability and health. Geneva, Switzerland: Author.
- World Health Organization. (2006). The world health report: 2006. Geneva, Switzerland: Author.
- National Organization on Disability. http://www.nod.org
- International Usability Professionals Association—World Usability Day. http://www.worldusabilityday.org
- World Health Organization—International Classification of Functioning, Disability, and Health. http://www.who.int/classification/icf
- Kaiser Family Foundation. http://www.kaisernetwork.org
- The Arc. http://www.thearc.org
- Consortium for Citizens with Disabilities. http://www.c-c-d.org
- American Association on Intellectual and Developmental Disabilities (formerly AAMR). http://www.aaidd.org
- Institute for Independent Living. http://www.independentliving.org/
- National Family Caregivers Association. http://www.nfcacares.org/