Subaverage intellectual ability that is present from birth or infancy and is manifested by abnormal development, learning difficulties, and problems in social adjustment. A standardized intelligence test is a common method of identification. Individuals with IQ scores of 53–70 are usually classified as having mild intellectual disability and are able to learn academic and prevocational skills with some special education. Those with scores of 36–52 are classified as having moderate intellectual disability and are able to learn functional academic skills and undertake semiskilled work under supervised conditions. Those in the severe (21–35) and profound (below 21) ranges require progressively more supervision or full-time custodial care. Intellectual disability can be caused by genetic disorders (such as Down syndrome), infectious diseases (such as meningitis), metabolic disorders, poisoning from lead, radiation, or other toxic agents, injuries to the head, and malnutrition.
Learn more about intellectual disability with a free trial on Britannica.com.
Disability is a lack of ability relative to a personal or group standard or norm. In reality there is often simply a spectrum of ability. Disability may involve physical impairment, sensory impairment, cognitive or intellectual impairment, mental disorder (also known as psychiatric or psychosocial disability), or various types of chronic disease. A disability may occur during a person's lifetime or may be present from birth.
Disability may be seen as resulting directly from individuals, in which case the focus is typically on aspects of those individuals and how they could function better. This view is associated with what is generally termed a medical model of disability. Alternatively, the interaction between people and their environment/society may be emphasized. Here, the focus may be on the role of society in labeling some people as having a disability relative to others, while causing or maintaining disability in those people through attitudes and standards of accessibility that favor the majority (a prejudice dubbed "able-ism"). This view is commonly associated with a human rights or social model of disability.
On December 13, 2006, the United Nations formally agreed on the Convention on the Rights of Persons with Disabilities, the first human rights treaty of the 21st century, to protect and enhance the rights and opportunities of the world's estimated 650 million disabled people. Countries that sign up to the convention will be required to adopt national laws, and remove old ones, so that persons with disabilities would, for example, have equal rights to education, employment, and cultural life; the right to own and inherit property; not be discriminated against in marriage, children, etc; not be unwilling subjects in medical experiments.
In 1976, the United Nations launched its International Year for Disabled Persons (1981), later re-named the International Year of Disabled Persons. The UN Decade of Disabled Persons (1983-1993) featured a World Programme of Action Concerning Disabled Persons. In 1979, Frank Bowe was the only person with a disability representing any country in the planning of IYDP-1981. Today, many countries have named representatives who are themselves individuals with disabilities. The decade was closed in an address before the General Assembly by Robert Davila. Both Bowe and Davila are deaf. In 1984, UNESCO accepted sign language for use in education of deaf children and youth.
With its origins in the US civil rights and consumer movements of the late 1960s, the movement and its philosophy have since spread to other continents influencing people's self-perception, their ways of organizing themselves and their countries' social policy.
In 2006, the Extremity Games was formed for people with physical disabilities, specifically limb loss or limb difference, to be able to compete in extreme sports. The College Park Industries, a manufacturer of prosthetic feet, organized this event to give disabled athletes a venue to compete in this increasingly popular sports genere also referred to as action sports. This annual event held in the summer in Orlando, FL includes competitions in skateboarding, wakeboarding, rock climbing, mountain biking, surfing, moto-x and kayaking.
Current issues and debates surrounding 'disability' include social and political rights, social inclusion and citizenship. In developed countries the debate has moved beyond a concern about the perceived cost of maintaining dependent people with a disability to an effort to find effective ways of ensuring people with a disability can participate in and contribute to society in all spheres of life.
Many are concerned, however, that the greatest need is in developing nations -- where the vast bulk of the estimated 650 million persons with disabilities reside. A great deal of work -- from basic physical accessibility through education to self-empowerment and self-supporting employment -- is needed.
In the past few years, disability rights activists have also focused on obtaining full sexual citizenship for the disabled. There is the great marathon for disabled people in June 2008.
The International Classification of Functioning, Disability and Health (ICF), produced by the World Health Organization, distinguishes between body functions (physiological or psychological, e.g. vision) and body structures (anatomical parts, e.g. the eye and related structures). Impairment in bodily structure or function is defined as involving an anomaly, defect, loss or other significant deviation from certain generally accepted population standards, which may fluctuate over time. Activity is defined as the execution of a task or action. The ICF lists 9 broad domains of functioning which can be affected:
(see also List of mental disorders)
The introduction to the ICF states that a variety of conceptual models has been proposed to understand and explain disability and functioning, which it seeks to integrate.
The medical model is presented as viewing disability as a problem of the person, directly caused by disease, trauma, or other health condition which therefore requires sustained medical care provided in the form of individual treatment by professionals. In the medical model, management of the disability is aimed at "cure", or the individual’s adjustment and behavioral change that would lead to an "almost-cure" or effective cure. In the medical model, medical care is viewed as the main issue, and at the political level, the principal response is that of modifying or reforming healthcare policy.
The social model of disability sees the issue of "disability" mainly as a socially created problem, and basically as a matter of the full integration of individuals into society (see Inclusion (disability rights)). In this model disability is not an attribute of an individual, but rather a complex collection of conditions, many of which are created by the social environment. Hence, in this model, the management of the problem requires social action, and thus, it is the collective responsibility of society at large to make the environmental modifications necessary for the full participation of people with disabilities in all areas of social life. The issue is both cultural and ideological, requiring individual, community, and large-scale social change. Viewed from this perspective equal access for people with impairment/disability is a human rights issue of major concern.
The American Psychological Association style guide states that, when identifying a person with an impairment, the person's name or pronoun should come first, and descriptions of the impairment/disability should be used so that the impairment is identified, but is not modifying the person. Improper examples would be "A Borderline, a "Blind Person." For instance: people with/who have Down syndrome, a man with/who has schizophrenia (instead of a Schizophrenic man), and a girl with paraplegia/who is paraplegic. It also states that a person's adaptive equipment should be described functionally as something that assists a person, not as something that limits a person, e.g. "a woman who uses a wheelchair" rather than is "in" it or is "confined" to it.
A similar kind of 'people first' terminology is also used in the UK, but more often in the form 'people with impairments' (e.g. 'people with visual impairments', etc.). However, in the UK, the term 'disabled people' is generally preferred to 'people with disabilities'. It is argued under the social model that while someone's impairment (e.g. having a spinal cord injury) is an individual property, 'disability' is something created by external societal factors such as a lack of wheelchair access to their workplace.. This distinction between the individual property of impairment and the social property of disability is central to the social model. The term 'disabled people' as a political construction is also widely used by international organisations of disabled people, such as Disabled Peoples' International (DPI).
Many books on disability and disability rights point out that 'disabled' is an identity that one is not necessarily born with, as disabilities are more often acquired than congenital. Some disability rights activists use an acronym TAB, "Temporarily Able-Bodied", as a reminder that many people will develop disabilities at some point in their lives, due to accidents, illness (physical, mental or emotional), or late-emerging effects of genetics.
The late Prime Minister Olof Palme of Sweden, speaking at the Stanford University Law School in the 1970s, summed up the divergence between U.S. and Swedish attitudes towards people with disabilities:
Palme maintained that if it cost the country $US 40,000 per year to enable a person with a disability to work at a job that paid $40,000, the society gained a net benefit, because the society benefited by allowing this worker to participate cooperatively, rather than to be a drain on other people's time and money.
The US Rehabilitation Act of 1973 requires all organizations that receive government funding to provide accessibility programs and services. A more recent law, the 1990 Americans with Disabilities Act (ADA), which came in to effect in 1992, prohibits private employers, state and local governments and employment agencies and labor unions from discriminating against qualified individuals with disabilities in job application procedures, hiring, firing, advancement, compensation, job training, or in the terms, conditions and privileges of employment. This includes organizations like retail businesses, movie theaters, and restaurants. They must make "reasonable accommodation" to people with different needs. Protection is extended to anyone with (A) a physical or mental impairment that substantially limits one or more of the major life activities of an individual (B) a record of such an impairment or (C) being regarded as having such an impairment. The second and third critiera are seen as ensuring protection from unjust discrimination based on a perception of risk, just because someone has a record of impairment or appears to have a disability or illness (e.g. features which may be erroneously taken as signs of an illness).
According to the 2000 U.S. Census, the African American community has the highest rate of disability at 20.8 percent, slightly higher than the overall disability rate of 19.4%. Although people have come to better understand and accept different types of disability, there still remains a stigma attached to the disabled community. African Americans with a disability are subject to not only this stigma but also to the additional forces of race discrimination. African American women who have a disability face tremendous discrimination due to their condition, race, and gender. Doctor Eddie Glenn of Howard University describes this situation as the "triple jeopardy" syndrome.
The US Social Security Administration defines disability in terms of inability to perform substantial gainful activity (SGA), by which it means “work paying minimum wage or better”. The agency pairs SGA with a "listing" of medical conditions that qualify individuals for benefits.
The demography of disability is difficult. Counting persons with disabilities is challenging. That is because disability is not just a status condition, entirely contained within the individual. Rather, it is an interaction between medical status (say, having low vision or being blind) and the environment.
Estimates of worldwide and country-wide numbers of individuals with disabilities are problematic. The varying approaches taken to defining disability notwithstanding, demographers agree that the world population of individuals with disabilities is very large. The World Health Organization, for example, estimates that there are as many as 600 million persons with disabilities. In the United States, Americans with disabilities constitute the third-largest minority (after persons of Hispanic origin and African Americans); all three of those minority groups number in the 30-some millions in America. According to the U.S. Bureau of the Census, as of 2004, there were some 32 million disabled adults (aged 18 or over) in the United States, plus another 5 million children and youth (under age 18). If one were to add impairments -- or limitations that fall short of being disabilities -- Census estimates put the figure at 51 million.
There is also widespread agreement among experts in the field that disability is more common in developing than in developed nations.
Costs of disability pensions are steadily growing in Western countries, mainly European and the United States. It was reported that in the UK, expenditure on disability pensions accounted for 0.9% of Gross Domestic Product (GDP) in 1980, but two decades later had reached 2.6% of GDP. Several studies have reported a link between increased absence from work due to sickness and elevated risk of future disability pension.
A study by researchers in Denmark suggests that information on self-reported days of absence due to sickness can be used to effectively identify future potential groups for disability pension. These studies may provide useful information for policy makers, case managing authorities, employers, and physicians.
Private, for-profit disability insurance plays a role in providing incomes to disabled people, but the nationalized programs are the safety net that catch most claimants.
Assistive Technology (AT) is a generic term for devices and modifications (for a person or within a society) that help overcome or remove a disability. The first recorded example of the use of a prosthesis dates to at least 1800 BC.
A more recent notable example is the wheelchair, dating from the 17th century. The curb cut is a related structural innovation. Other modern examples are standing frames, text telephones, accessible keyboards, large print, Braille, & speech recognition computer software. People with disabilities often develop personal or community adaptations, such as strategies to suppress tics in public (for example in Tourette's syndrome), or sign language in deaf communities. Assistive technology or interventions are sometimes controversial or rejected, for example in the controversy over cochlear implants for children.
Further, organisations such as AbilityNet and U Can Do IT, have been established to provide assessment services which determine which assistive technologies would best assist an individual client, and also to train people with disabilities in how to use computer-based assistive technology.
Through the use of the internet, networking between groups and disability charities is now becoming more and more productive. It is now a widely held belief that should it be possible to unite various interest groups, primarily Physical, Sensory and Learning disabilities, it would be possible to turn what is considered to be a minority group, into a major force for change. However uniting such a diverse group of disabilities, often with conflicting interests, may prove difficult. For further information on disability organisations based in the UK, please see:
Disability insurance directory.(Who writes what: National Underwriter's guide to life & health coverages and services)
Aug 16, 2004; Producers rely on National Underwriter's Who Writes What, an Annual Directory of companies and brokers and the coverages they...
Disability rights in Cambodia: using the Convention on the Rights of People with Disabilities to expose human rights violations.
Jan 01, 2009; Abstract: In Cambodia, the percentage of the population living with disabilities is one of the highest in the world. At least...