Unit 1: Understanding Disability

1.1 Historical development in understanding disability

1.2 Emerging trends: Concept and Definition of Impairment, Disability, Handicap (ICIDH) and Functioning (ICF)

1.3 Definition and Categories of Disability as per National laws

1.4 Prevalence and demographic profile

1.5 Causes and prevention of disability











1.1          Historical development in understanding disability

Disability is not a new concept and not something that has emerged as a result of increasing numbers of people affected. Rather, disability is an ancient concept that has existed for as long as people have existed. Although disability has not changed, our views of the meaning of disability have changed over time-for the better.

Early Views of Disability

In the medieval era, disability was considered a punishment from God for one’s sin or misbehavior or that of one’s ancestors. Others over the centuries have viewed disability as the work of the devil. Disability was seen as a failure, deformity or defect of the individual. As a result of the myths about disability, people with disabilities were feared and often stigmatized, shunned, abused, or condemned. People with visible disabilities were even used for entertainment (e.g., court jesters or oddities in circuses and freak shows). Children and adults with severe disability were kept at home, isolated and hidden from public view. They were often denied what others received, including education, care, employment, and a place in the family or in society. Disability was viewed as inability and those with disabilities were often viewed as a burden to their families and to society as a whole.

People with disabilities have been considered sick or unhealthy. Being healthy and having a disability have been perceived as a contradiction in terms. Disability was seen as an issue blamed on the individual with a disability. Quality of life of individuals with disability was often seen---and still is by some---to be poor by others who have very negative views about disability, even though only an individual can determine the quality of life of his or her own life.

Changing Views about Disability

By the 1800s disability began to be viewed as an issue that had individual health and public health implications, as well as social and policy implications. Disability was seen as a medical problem due to disease, trauma, or other health conditions. This generally led to the medical model of disability, which viewed disability as an issue of the person with a disability. The goal of medical management was cure of the disabling condition or modification of behaviors of the individual with a disability. The medical model viewed physicians as the experts who knew what was best for those with disabilities. Those with disabilities were not seen as capable of knowing what they needed in the way of health care and other services.

More recently, disability has been viewed as a result of environmental and societal factors that serve as barriers to the ability of persons with disabilities to participate fully in their communities or families or to obtain the care and services they need. Individuals with disability, their families, and advocacy groups have viewed disability as a consequence of an inaccessible environment and rejected the medical model in favor of other models, such as the social and biopsychosocial models of disability that address barriers to health care from different perspectives.




1.2 Emerging trends: Concept and Definition of Impairment, Disability, Handicap(ICIDH) and Functioning(ICF)

Education is a lifelong process involving many planned and unplanned experiences that enable children and adults alike to develop and learn through interaction with the society and culture in which they live. It involves experiences at all stages of life, from infancy through to old age.
Education also involves adaptations to society and culture. With all the combinations of life events, adaptation will mean that each person is subject to a unique set of learning and problem solving experiences that constitute an understanding of the world and the events that take place in it. However, if we limit our attendance to intentional learning and instruction of children across the time from preschool to tertiary education, this would involve learning from a curriculum that has been determined by the central or state education authority.
There are many children who, for some reason, are unable to take full advantage of the school curriculum as it is normally offered. For these children special arrangements must be made to ensure that they receive the opportunities and experiences, which will help them to learn and develop to the extent of their capabilities.
To help us to deal with the question of who these children may be, we need first to understand a few adjectives which you will, no doubt, encounter in your reading about children with special needs. These adjectives are ‘impaired’, ‘disabled’ and ‘handicapped’. Over the years, these terms have often been used interchangably and at times carelessly. However, they have specific meanings and conceptual differences, which are important for us to know.

International Classification of Impairment, Disability and Handicap as given by World Health Organisation (WHO)

The World Health Organisation (WHO) has defined the terms ‘Impairment’, ‘Disability’ and ‘Handicap’ in 1980 through the publication of the International Classification of Impairments, Disabilities and Handicaps (ICIDH), which is a manual of classification relating to the consequences of diseases. The ICIDH proposes the concepts and definitions of Impairment, Disability and Handicap, and discusses the relation between these dimensions. It is based on a linear model (Figure 1) implying progression from disease, impairment and disability to handicap.


Definitions of Impairment, Disability, Handicap

Impairment: According to the ICIDH, impairment is any loss or abnormality of psychological, physiological or anatomical structure or functions, generally taken to be at organ level

Impairment is damage to tissue due to disease or trauma. A person who has poor or no vision due to damage to retina or optic nerve may be said to have a visual impairment.

Disability: Disability has been defined as any restriction or lack of ability (resulting from an impairment) to perform an activity in the manner or within the range considered normal for a human being, generally taken to be at the level of the individual.

Disability denotes the consequences of impairment in terms of functional performance and activity by the individual. A person who has an optic nerve or retinal damage would have limitations in performing those tasks that requires the use of eyesight.

Handicap: The ICIDH defines Handicap as a disadvantage for an individual, resulting from an impairment or disability, which limits or prevents fulfillment of a role that is normal (depending on age, sex and social cultural factors) for that individual.


Concerned with



Abnormalities of body structure, organs, appearance and system functioning

Disturbances at organ / tissue level


Limitations/loss of functional performance and activities

Disturbance at personal level


Disadvantages resulting from impairment and disabilities

Situation specific limitations

In order to understand children with special needs we must know the different adjectives or terms by which they are often described. Impairment, Disability and Handicap are terms, which are frequently used interchangeably. However, there are conceptual differences among the terms.

The differences have been clearly outlined in the definitions of each of the terms by WHO in the International Classification of Impairment, Disability and Handicaps.
represents exteriorization of a pathological state and occurs at tissue level.
Disability refers to excesses or deficiencies of customarily expected activity, performance and behaviour, and is located at the level of the person.
Handicap reflects the consequences for the individual - cultural, social, economic and environmental - that stem from the presence of impairment and disability.

1.3          Definition and Categories of Disability as per National laws

There are innumerable types of disabilities that can affect a human being. Some of these conditions are more common than others. Some of the types of disabilities are recognized by the government in order to provide disability benefits to the needy ones. Often people wonder what are the disabling conditions that are more prevalent. Here is the list of 21 disabilities that have been identified under the RPWD Act 2016 of India.

1. Blindness

Blindness is defined as the state of being sightless. A blind individual is unable to see. In a strict sense the word blindness denotes the condition of total blackness of vision with the inability of a person to distinguish darkness from bright light in either eye.

2. Low-vision

Low-vision means a condition where a person has any of the following conditions, namely:

1.     visual acuity not exceeding 6/18 or less than 20/60 upto 3/60 or upto 10/200 (Snellen) in the better eye with best possible corrections; or

2.     limitation of the field of vision subtending an angle of less than 40 degree up to 10 degree.

3. Leprosy Cured Persons

Leprosy, also known as Hansen’s disease (HD), is a chronic infectious disease caused by a bacteria called Mycobacterium leprae. The disease mainly affects the skin, the peripheral nerves, mucosal surfaces of the upper respiratory tract and the eyes. Leprosy is known to occur at all ages ranging from early infancy to very old age. About 95% of people who contact M. Leprea do not develop the disease.

4. Hearing Impairment

Hearing impairment is a partial or total inability to hear. It is a disability which is sub-divided in two categories of deaf and hard of hearing.

5. Locomotor Disability

Strictly speaking Locomotor Disability means problem in moving from one place to another — i.e. disability in legs. But, in general, it is taken as a disability related with bones, joints and muscles. It causes problems in person’s movements (like walking, picking or holding things in hand etc.)

6. Dwarfism

Dwarfism is a growth disorder characterized by shorter than average body height.

7. Intellectual Disability

Intellectual disability, also known as general learning disability and mental retardation (MR), is a condition characterized by significant limitation both in intellectual functioning (reasoning, learning, problem solving) and in adaptive behavior which covers a range of every day, social and practical skills.

8. Mental Illness

Mental illness or mental disorder refers to a substantial disorder of thinking, mood, perception, orientation or memory that grossly impairs judgment, behavior, capacity to recognize reality or ability to meet the ordinary demands of life. But it does not include retardation which is a condition of arrested or incomplete development of mind of a person, specially  characterized by sub-normality of intelligence.

9. Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a neurological and developmental disorder which affects communication and behavior. Autism can be diagnosed at any age. But still it is called a “developmental disorder” because symptoms generally appear in the first two years of life. Autism affects affects the overall cognitive, emotional, social and physical health of the affected individual.

10. Cerebral Palsy

Cerebral Palsy (CP) is a disabling physical condition in which muscle coordination is impaired due to damage to the brain. It occurs at or before child birth. Cerebral Palsy is not a progressive condition; meaning it does not get worse with time. However, muscle disuse could increase the extent of disability over the period of time. At present there is no cure available for this condition. Thus, Cerebral Palsy is incurable and life-long condition, at present.

11. Muscular Dystrophy

Muscular Dystrophy (MD) is a group of neuromuscular genetic disorders that cause muscle weakness and overall loss of muscle mass. MD is a progressive condition; meaning that it gets worse with the passage of time.

12. Chronic Neurological Conditions

Examples of Chronic Neurological Conditions:

1.     Alzheimer’s disease and Dementia

2.     Parkinson’s disease

3.     Dystonia

4.     ALS (Lou Gehrig’s disease)

5.     Huntington’s disease

6.     Neuromuscular disease

7.     Multiple sclerosis

8.     Epilepsy

9.     Stroke

13. Specific Learning Disabilities

Specific Learning Disabilities is a group of disabling conditions that hampers a person’s ability to listen, think, speak, write, spell, or do mathematical calculations. One or more of these abilities may be hampered.

14. Multiple Sclerosis

In Multiple Sclerosis (MS), the immune system of body attacks the Central Nervous System, which includes brain and spinal cord. As a result of MS, the myelin sheath covering on neurons gets damaged. This exposes the nerve fiber and causes problems in the information flow through nerves. With time, MS can lead to the permanent damage to nerves.

15. Speech and Language Disability

A permanent disability arising out of conditions such as laryngectomy or aphasia affecting one or more components of speech and language due to organic or neurological causes.

16. Thalassemia

Thalassemia is a genetically inherited blood disorder which is characterized by the production of less or abnormal hemoglobin. As we know, hemoglobin is a protein found in Red Blood Cells. Hemoglobin is responsible for carrying oxygen around in the body. Thalassemia results in large numbers of red blood cells being destroyed, which leads to anemia. As a result of anemia, person affected with Thalassemia will have pale skin, fatigue and dark coloration of urine.

17. Hemophilia

Hemophilia is a blood disorder characterized by the lack of blood clotting proteins. In the absence of these proteins, bleeding goes on for a longer time than normal. Hemophilia almost always occurs in males and they get it from their mothers. Females are rarely affected with hemophilia.

18. Sickle Cell Disease

Sickle Cell Disease is a group of blood disorders that causes red blood cells (RBCs) to become sickle-shaped, misshapen and break down. The oxygen-carrying capacity of such misshapen RBCs reduce significantly. It is a genetically transferred disease. Red Blood Cells contain a protein called hemoglobin. This is the protein that binds oxygen and carry it to all the parts of the body.

19. Multiple Disabilities including Deaf-blindness

Multiple Disabilities is the simultaneous occurrence of two or more disabling conditions that affect learning or other important life functions. These disabilities could be a combination of both motor and sensory nature.

20. Acid Attack Victims

An acid attack victim means a person disfigured due to violent assaults by throwing of acid or similar corrosive substance.

21. Parkinson’s disease

Parkinson’s disease (PD) is Central Nervous System disorder which affects movement. Parkinson’s disease is characterized by tremors and stiffness. It is a progressive disease, which means that it worsens with time. There is no cure available at present.

1.4 Prevalence and demographic profile

Prevalence of a condition or disability in determined by epidemiology.

Epidemiology is a science concerned with the study of factors that influence the occurrence and distribution of disease, defect, disability, or death in aggregation of individuals. Epidemiology involves making a determination or estimate of the number of cases of some condition in a population. In addition, it attempts to relate this estimate to other classification of population, such as age, sex, and social class.

A good epidemiologist depends upon the definition of the condition in question. If the condition is poorly or vaguely defined, there will be a problem with the estimates of its occurrence.

An epidemiologist uses two methods for estimating the occurrence of a condition in a population: the incidence rate and the prevalence rate.

Difference between Incidence and Prevalence

Incidence refers to the number of new cases in population during a specified period of time. Prevalence refers to the total number of cases in a population group during a specified period of time.

The Count

As per the Census 2011, 

·        In India out of the 121 Cr population, 2.68 Cr persons are ‘disabled’ which is 2.21% of the total population.

·        Among the disabled population 56% (1.5 Cr) are males and 44% (1.18 Cr ) are females. In the total population, the male and female population are 51% and 49% respectively. 

·        Majority (69%) of the disabled population resided in rural areas (1.86 Cr disabled persons in rural areas and 0.81 Cr in urban areas). In the case of total population also, 69% are from rural areas while the remaining 31% resided in urban areas.

·        The percentage of disabled population among males and females are 2.41% and 2.01% respectively. At all India level as well as disaggregated by various social groups, the proportion of disabled in the corresponding population is higher for males than females.

·        During 2001 – 2011, an increase in the number of disabled persons was observed both in rural and urban areas and also among males and females. The share of disabled persons in the total population, as well as in the male and female population also increased during this period. 

·        The percentage of disabled to the total population increased from 2.13% in 2001 to 2.21% in 2011. In rural areas, the increase was from 2.21% in 2001 to 2.24% in 2011 whereas, in urban areas, it increased from 1.93% to 2.17% during this period. The same trend was observed among males and females during this period.

·        In India, 20% of the disabled persons are having disability in movement, 19% are with disability in seeing, and another 19 % are with disability in hearing. 8% has multiple disabilities.




1.5       Causes and prevention of disability


Risk factors for the disabilities:

Communicable diseases (Infectious diseases) such as lymphatic filariasis, tuberculosis, HIV/AIDS, and other sexually transmitted diseases; neurological consequences of some diseases such as encephalitis, meningitis, and childhood cluster diseases (such as measles, mumps, and poliomyelitis) contribute to disability.

Non communicable diseases (NCDs)

·        Chronic diseases such as diabetes, cardiovascular disease, arthritis and cancer cause the majority of long-term disabilities. The increase in NCDs observed in all parts of the world, will have a profound effect on disability.

·        Lifestyle choices and personal behavior such as obesity, physical inactivity, tobacco use, alcohol consumption, illicit drugs that lead to non communicable diseases are also becoming major contributing factors;

·        Air pollution, occupational disease, poor water supply, sanitation, and personal and domestic hygiene, malnutrition also contribute for disability.

Injuries due to road traffic accidents, occupational injury, violence, conflicts, falls and landmines have long been recognized as contributors to disability.

Mental health problems– mental health retardation and mental illness are the causes of mental disability. In more than 50% cases mental retardation has been reported to be caused by serious illness or head injury in the childhood and birth defects. Mental retardation was observed mostly at birth or at very early ages of life while the problem of mental illness is more of an old age problem.

Those with lower education levels, lower incomes, and those who are unemployed were also more likely to suffer a disability.

There is higher risk of disability at older ages.



It is extremely important that the women undertake adequate and effective preventive measures during their pregnancy and immediate postnatal period and also for their children especially during the early childhood period, in order to significantly reduce the incidence of impairment and disabilities in them. Therefore, in this chapter examples of easily understood primary preventive measures, for mother and child are summarized.

General preventive measure

1.     Marriage between very close blood relations like uncle, niece, first cousin should be avoided for prevention of hereditary disorders.

2.     Avoid pregnancies before the age of 18 years and after the age of 35 years.

3.     Consult a doctor before planning the pregnancy;

Care during pregnancy

1.     Avoid hard physical work such as carrying heavy loads, especially in fields, and other accident - prone activities such as walking on slippery ground or climbing stools and chairs.

2.     Avoid unnecessary drugs and medications. Even the normally considered safe drugs which are sold commonly can potentially cause serious defects in an unborn child.

3.     Avoid smoking, chewing tobacco, consuming alcohol and narcotics.

4.     Avoid X - rays, and exposure to any kind of radiation.

5.     Avoid exposure to illnesses like measles, mumps etc, especially during the first 3 months of pregnancy.

6.     Avoid sexual contact with a person having venereal disease.

7.     Take precautions against lead poisoning.

8.     Avoid too much use of ‘Surma’ and ‘Kohl’.

9.     Eat a well-balanced and nourishing diet supplemented with green leafy vegetables, proteins and vitamins.

10.                       All women of the child bearing age need 0.4mg of folic acid daily. It is also available in folic acid plus iron tablets which should be taken for at least 3 months during the third trimester when the risk of developing iron deficiency anemia is greatest.

11.                       Ensure weight gain of at last 10 kgs. Have regular medical checkups.

12.                       All pregnant women should be given tetanus injection.

13.                       Woman at ‘high - risk’, whose weight is < 38 Kg, height is less than 152 cm, weight gain during pregnancy <6 kg or who is severly anaemia c (Hb < 8mg), having frequent pregnancies, having a history of miscarriage/ abortion/premature deliveries, must get expert prenatal care so as to have a normal baby.

14.                       Must consult a doctor, in case of edema (swelling) of feet, persistent headache, fever, difficulty or pain in passing urine, bleeding from the vagina, and yellowness of eyes (jaundice)

Care at the time of birth

1.     Delivery must be conducted by trained personnel, preferably in a hospital where all facilities are available.

2.     If a baby does not cry immediately after birth, resuscitation measures should be undertaken at once.

3.     Babies born prematurely and with a low birth weight (<2.5 Kg) may need Neonatal Intensive Care.

4.     If the baby’s head appears to be abnormally small or large then a physician should be consulted, preferably a pediatrician. The approximate head size for a male child at birth is 35 cm and for female child is 34.5 cm.

5.     To protect a child from infections, breast - feeding must be started immediately after birth. First milk (colostrum) must be fed to the baby and should not be thrown away, as it has antibodies which are protective.

Early childhood care

1.     Do not allow a child’s temperature to rise above 101 degree F because of any reason. It can cause febrile seizures

2.     If a child gets a fit take him to doctor immediately.

3.     Every child should be immunized against infectious diseases as per the recommended schedule of immunization.

4.     Do not allow a child to have too much contact with paint, newsprint ink, lead etc. as they are toxic.

5.     Take precautions against head injury, and other accidents.

6.     Ensure that the child gets a well-balanced diet and clean drinking water.

7.     Introduce additional foods of good quality and in sufficient quantity when the child is 4 -6 months old.

8.     Vitamin A deficiency and its consequences including night blindness can be easily prevented through the use of Vitamin A supplementation.

9.     Protect a child from Meningitis and Encephalitis by providing a hygienic environment which is free of overcrowding.

10.                       Common salt must be iodized as a precaution against goiter and cretinism.

11.                       Do not allow a child to use hairpins, matchsticks and pencils, to remove wax from the ears.

12.                       Use ear protectors to reduce the exposure to high levels of noise, if children are living or working in a noisy environment.

13.                       Do not slap a child over the face as this may lead to injury of the eardrum and consequent hearing loss