The landmark United Nations Convention on Persons with disabilities also brings to the fore two perspectives on disability: one is the perspective of global public health, and the other is the perspective of human rights. Although these perspectives may seem to be in conflict to some, we see them as complementary. From a public health perspective, childhood disability is an adverse condition that, like influenza or lead toxicity, should be investigated and monitored so that it can be prevented. From this perspective, there is a need for valid estimates of the number of children affected by disability, investigations of risk factors and causes, and scientific bases for determining how to mitigate risk factors to prevent disability ( Maureen and Carissa, 2009).

In contrast, from a human rights perspective, the focus is not on prevention of disability but on the dignity of all persons with disabilities and the need for policies to ensure equal protection of the rights of persons with and without disabilities. From a child rights or protection perspective, childhood disability is not merely a medical condition to be prevented but also the result of social conditions that do not accommodate the range of needs for support that children have. Furthermore, children with disabilities are considered vulnerable members of society who would benefit from policies designed to ensure their equal rights and protection against discrimination (UNICEF, 2008). From both the above perspectives, it becomes imperative to prevent and intervene in childhood disabilities.

Ghosh (1995) writes in an editorial that many babies do not get adequate food between 6 months and 2 years of age, a time when they are totally dependent on the mother or a mother substitute for feeding. Many mothers are busy and might be away from home, in which case feeding is often left to an older sibling or another family member. There are constraints of time and fuel and often unsuitable snacks are bought and fed to the child instead of home cooked food. She refers to the period between 6 months and 2 years as a period of perpetual hunger. There is widespread preference for liquids (grossly diluted milk, tea, dal water, vegetable soup, fruit juice, etc.) over semisolids and a majority of health and ICDS workers help to strengthen that belief by wrong advice in favor of these liquids, which have hardly any nutritional value. Malnutrition during this crucial period is certainly not due to poverty and lack of family resources, but due to lack of knowledge and not giving priority to young child feeding.

If care and caution is exercised during prenatal, post-natal and early childhood years, WHO estimates that almost 70 percent of disabilities could be prevented. Most of the disabilities are caused due to diseases, infections, poor environmental sanitation and hygiene, malnutrition, faulty child rearing practices, ignorance and lack of knowledge about simple ways of preventing diseases and disablement (Chopra, 1997). In a study by Chakraborty and Dutt (2004), 55% of the disabilities were acquired indicating that more than half of the disabilities could have been prevented. In Safdarjung hospital, New Delhi it was found that 45.5% of the disabilities could have been prevented.

Earlier an exceptionality is recognized and intervention initiated, greater would be the chances of arresting the disability from deteriorating further and coming in the way of normal development of the child. With early detection of disabilities followed by effective intervention, one can arrest future deterioration of the impairment (Chopra, G. 1997).

Developmental examination is a clinical procedure designed to evaluate the level of development reached by a child at particular point in time and to detect any significant deviations from the normal. It usually includes an interview with the parents, structured observations and the administration of specific tasks or tests. It should be done by a person who understands normal child development and its variations and is properly trained .The developmental examination in itself may not necessarily be diagnostic .Experience has shown that by the end of first year of life , all major impairments can be detected and any persisting minor impairment must be regarded as significant (Singh P.D,1992). Developmental surveillance is recommended for all well-child visits. Surveillance is defined as a flexible, longitudinal, and continuous process that includes eliciting and attending to parents’ concerns, maintaining a developmental history, making accurate and informed observations, identifying the presence of risk and protective factors, and documenting the process and findings. Standardized screening is recommended at least three times during the first 3 years of life to ensure early recognition and referral of young children with developmental delay. A standardized developmental screening test should be administered at the 9, 18, and 30 month (or 24-month) visits (Martin, 2006). Early identification of developmental disorders is critical to the well-being of children and their families. It is an integral function of the primary care medical home and an appropriate responsibility of all pediatric health care professionals. This statement provides an algorithm as a strategy to support health care professionals in developing a pattern and practice for addressing developmental concerns in children from birth through 3 years of age. The authors recommend that developmental surveillance be incorporated at every well-child preventive care visit. Any concerns raised during surveillance should be promptly addressed with standardized developmental screening tests. In addition, screening tests should be administered regularly at the 9-, 18-, and 30-month visits (Duby and Lipkin, 2006).

In an attempt to study early predictors of neurodevelopmental outcome in high risk infants, Godbole, Barve and Chaudhari (1997) reported that babies with an inability to achieve social smile and abnormal neurobehavior at three months age and absence of pulling to sit position, transfer of objects and voluntary reach at six months age, warrant early intervention. These babies remained delayed at one year. The specificity of each of these items was 100%. These items had a positive predictive value of 100%. These items are easy to elicit, do not require any special kit or elaborate training. Hence these items can be tested even by those working at the primary level.

Belmont (1984) conducted a study in 10 sites in nine developing countries viz. Bangladesh, Brazil, India, Malaysia, Nepal, Pakistan, Philippines, Sri Lanka and Zambia. The major focus of the Pilot study was to determine whether it would be possible, in developing countries, to identify children with severe mental retardation and other disability conditions, by means of short questionnaires. This was accomplished by house-to-house survey, which was followed by professional examination. The Ten Questions Screen was tested and found to be sensitive for detecting severe mental retardation. However, it was also found to generate excess false positives.

To determine whether late onset of canonical babbling could be used as a critical criterion to determine risk of hearing impairment , vocalization samples were obtained longitudinally from 94infants with normal hearing and 37 infants with severe to profound hearing impairment. Parents were instructed to report the onset of canonical babbling (the onset of well formed syllables such as ‘da’,’na’).Infants with normal hearing produced canonical babbling 11 months, infants who were deaf failed to produce canonical babbling until 11months or older often well into 3rd year of life. The correlation between age of onset of the canonical stage and age of auditory amplification was 0.68, indicating that early identification and fitting of hearing aids is of significant benefit to infants learning language. The facts that there is no overlap in the distribution of the onset of canonical babbling between infants with normal hearing and infants with hearing impairment means that the failure of otherwise healthy infants to produce canonical babbling, before 11months of age should be considered a serious risk factor for hearing impairment and when observed should result in immediate referral for audiological evaluation (Eilers and Ollar, 1994).

Magnuson, Persson and Sundelin (2001) report that health surveillance is a part of secondary prevention. It is often performed in order to screen the population and detect health problems early, often in the pre-symptomatic period. It does not reduce the incidence of problem but can reduce the prevalence by shortening their duration or diminishing their impact through prompt and effective intervention at an early stage. The study also suggested that specific screening methods are more effective than top-to-toe clinical examinations by physicians.

Pediatricians should routinely and carefully elicit parent’s opinions and concerns regarding child’s development. Parents’ concerns are helpful adjuncts to routine developmental assessment and may be used to make appropriate referrals (Glascoe , 1999; Malhi and Singhi, 2002).

In a study, Maas (2000) reiterates that early detection of speech and language delays is preferable at least before the age of 4 years. The study reported that the most effective screening instruments are the ones that can be used in regular check ups.

Baroda citizens Council (1989) in Baroda Gujarat, undertook a project for “Prevention, Early Detection and Intervention of Childhood Disabilities in Baroda Slums” from 1983-1988. The objective of this project was identification in children between 0-15 yrs. From 325 slums of Baroda, as having major disabilities.

Co-ordination of services for medical and educational rehabilitation as well as prevention and management of disability was a major goal. In all, BCC project identified 1700 children as disabled from 325 slum pockets. Amongst these, 910 had locomotor disability, 181 visual, 90 hearing, 118 speech, 146 mental retardation and 255 had multiple handicap. Medical intervention was provided to 989 children, educational intervention to 518 children and a heavy input went into intervention on prevention and management of disabilities. The last part included public awareness campaigns, nutrition education, demonstrations, training of grass-root level workers, slide and film shows, child to child programmes and orientation of community people.

SAMADHAN in Delhi has identified early detection and intervention for children with mental handicap as one of its thrust areas. The project has a centre based early intervention programme, as well -as home based programmes. The project's experience showed that home based service delivery may not be successful unless it was supported by a centre based programme which could provide specialised services. The centre to children from 0-6 years, with special emphasis on the 0-3 age group. The services provided at the centre include assessments, individual programme planning based on the Jamaican adaptation of the Portage Model, educational and therapeutic interventions, creative activities and parent counselling. Special educators, teachers, a speech therapist, a physiotherapist and a part-time paediatrician provide the specialised services at the centre. With the successful establishment of the centre, SAMADHAN moved into home based service delivery for mentally handicapped children below the age of 5 years. The home based programme components include initial identification through surveys in low income areas which are carried out by teachers, diagnosis and assessment , parent training and counselling, support services from centre based specialists and community awareness building. The highlights of this programme is the training of motivated persons from the community to work as home visitors, who eventually transfer the skills of management of the disabled children to the parents. SAMADHAN's experience has shown that home based programmes for early identification and intervention have a lot of scope, particularly since such programmes involve the local community, and services can be provided by people with minimum qualifications. (Thomas M., 1992 )

The Centre for Special Education of the Spastics Society of India, Bangalore carries out early identification and home based, intervention programmes for children with cerebral palsy. The centre has brought out an illustrated parent training manual, based on the Portage model. The manual has been translated into the local language and is being used by parents, under the guidance of therapists from the centre.

TRAINING COMMUNITY WORKERS FOR EARLY DETECTION

A few researchers have shown that the skills required for early detection can be provided to community level workers through short training. Mathur and colleagues (1983) utilized AWW of ICDS for identifying handicap in youth and children and concluded that after training the AWW can help in detection of disabilities. NIPCCD undertook an experiment to train AWW in undertaking the responsibility of prevention, early detection and referral. This was conducted in collaboration with N1MHANS Banglore and NTVH Dehradun. In Banglore, 58 persons were trained (22 AWW, ANMs, 4 LHVs, 2 supervisors, 1 Gramsevika and 1 CDPO) for 3 days for early detection of mental handicap. These trainees detected 60 cases, of which 70% were correct. At NIVH Dehradun, 38 persons (27 AWW, 6 ANM, 5 LHVs) were trained for 4 days to detect visual impairments. They detected 38 cases with all correct diagnosis. (NIPCCD, 1989).

NIPCCD trained 34 AWW and 5 supervisors in Mehrauli ICDS block of Delhi on early detection of major disabilities. They identified 283 cases of children having one or the other disabilities. 32% had orthopaedic, 29% speech, 21% hearing 9% visual and 9% had mental retardation (NIPCCD, 1989). The conclusion of the NIPCCD experiment was that early detection does not require high degree of skill or expertise. Any functionary with rudimentary education can be trained in identifying "at risk" children, early signs of impairment and intervene by appropriate referral. Deprofessionalisation of service delivery i.e. service to be provided by Para-medical and non-professional worker is emerging as a growing need for organizing and maintaining early intervention services. (Kohli T., 1989)

In a project conducted in Jammu and Kashmir, community volunteers drawn from local community used the ten point questionnaire in a house to house survey to detect impairments and disabilities. Each disabled was examined by concerned specialist and mode of treatment decided and the programme recommended by the specialist. She was the functional link between the disabled and the specialist. This project covered a total of 88014 populations, including 30192 children. Number of children identified as having a disability was 1400. Of these 1199 were cross examined by specialists. The conclusions of this study were that it is possible to train community volunteers in detection and rehabilitation of disabled with proper support, supervision and monitoring systems. The ten question proforma of WHO proved effective in identifying disabled cases, (Gandotra V.K., 1988.)

In another study, Early detection of hearing impaired children was done in Haryana. The study highlighted the possibility of providing preventive and diagnostic services in remote areas using grass-root level workers. The children who were 'at risk' for developing speech and hearing problems were identified through door-to-door survey conducted by village volunteers covering 117 villages with a population of 68165 persons. The cases identified were followed up by medical and audio logical speech examination (Duggal S., 1988).

As part of the department of health funded evaluation of the first phase of the national health service newborn hearing screening programme in England, 45 parents whose children were correctly identified as deaf through the screening programme were interviewed about their experiences. The diagnostic period emerged as an important time for parents .This refers to the period of time that follows the referral from screen and starts with the first appointment at audiology for audio logical assessment .The diagnostic process was found to be hugely variable for each family , both objectively , eg in terms of number of appointments they had to attend and also attitudinally , e.g. some families perceived this period of time as a series of discrete events while others viewed it as a part of process that had started with the first screening event.(Tattersall , 2005)

In a study, 20 AWW were trained on developmental screening of infants and young children ( 6 weeks - 2 yrs.) and results compared with trained medical practioner. First evaluation did not show good mastering of skills by workers, but with retraining very good levels of proficiency were achieved with tester/author agreement of 97%. The authors felt an acute paucity of teaching materials, charts, video cassettes, slides etc.. The need for an illustrated manual in Hindi, containing clear, precise, unequivocal instructions can never be overemphasized. (Gupta and Patel, 1991).

Thirty AWW were trained on the use of NIMH Developmental Screening Test. Eighteen hours of training was imparted on the use of NIMH-DSS and early identification of M.H. Training covered information on growth and developmental stages and developmental delay, milestones in development, screening instrument and explanation of test items on DSS, demonstration on use of DSS, and assessment of 5 children using the DSS by each AWW. Each of the AWW used DSS on 30 children each. Total 600 children were screened. Of these, 19 cases of impairments were reported. There were 6 false positives, 5 false negatives and 570 true negatives found (Arya S., 1988).

Ten trained AWWs identified disabilities and instituted preventive measures like immunization and supplementary nutrition. Simultaneous independent verification by pediatricians was done and a repeat survey was conducted after 6 months as a follow up. Amongst the 1545 children, AWW identified disability in 126 subjects which were verified in 118 cases by pediatricians. In the repeat survey, 35 of the 74 children with visual disability, 4 of the 9 with orthopedic disability and 3 of the 7 with hearing disability could be managed satisfactorily. AWW can help in early detection an appropriate management of incipient and preventable childhood disabilities. (Mathur et al, 1995).

Children with problems were identified by the AWWs, which in most cases was correct, though in some cases they could not give specific medical terminology for the problem. A large scale screening of 0-15 yrs. children was conducted in 325 slums of Baroda. In all 1700 children were identified as disabled. After identification, medical and education intervention was provided. Intervention for prevention and management of disabilities was also disseminated to the community (Patel, 1989).

Detection methods that are rapid, simple and feasible for application in rural settings are required. Using the key informant approach we were able to quickly identify the major types of childhood disabilities. The key informant approach has the advantage of involving local people in the detection of disabilities thus bringing out participation by the community. These key informants can be further trained so that they can act as local resource personnel for provision of primary information, counseling and care for children with disabilities at the community level (Chakraborty and Dutt 2004).

Chopra ( 1997), trained 19 grass-root level early child care workers, viz the Anganwadi workers( AWW) of the Government of India’s Integrated Child Development scheme (ICDS) projects in Delhi on a specially developed module. The workers were found to have achieved a knowledge gain of 27% after the training. The trained workers did a house to house survey in 9 slum cluster of Delhi using the DSS and screened 3560 (0-6yr) children and detected 245(7%) cases of children with disabilities, impairments or ‘at risk’ factors. Chopra ( 2002) trained 53 workers. 15 AWW from urban ICDS project, 14 AWW from rural ICDS project, 12 LHV’s, 6 ANM’s and 6 were workers of NGO’s on early detection of disabilities in South Delhi. The AWWs from urban projects screened children from 6 slum pockets. The rural AWWs screened children from 4 rural areas of Delhi. The LHVs and ANMs screened children children coming to 10 MCW centres of south Delhi. The NGO workers screened children from 5 slum clusters of East and South Delhi. The AWWs displayed on an average, knowledge gains of 19%, Health workers showed a gain of 26% and NGO (Pratham, Deepalya, Manzil) workers a gain of 31%. The AWWs and health workers screened 4319 children identified 268 (6.3%) children with ‘at risk’ conditions/impairments/disability. Screening skills of 4 NGO workers from Pratham were assessed. They screened 400 children and reported a whooping 85 (22.5%) children with ‘at risk’ conditions/impairments/disability. The one worker from NGO Manzil screened 100 children and reported 26 (26%) cases of disability. To conclude, prevention and early detection in children is crucial to the children’s and their families well being. In a developing country of the size of India, we need methods of screening which are rapid and easy and can be used by grass root community worker. With little training, community workers can conduct mass surveillance and easily refer cases they detect in their community to primary health care facilities. The trained community worker can act as a bridge between the child who is showing signs of disability and needs help and the health care professional. Prevention and early detection of disability actually appeals the practical minded as it is in line with the age old dictum, ‘a stitch in time saves nine’ and ‘ prevention is better than cure’. Prevention and early detection of disability is far more efficacious as well as cost effective than providing rehabilitative services to a disabled person or the loss of a human resource due to disability.