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Correspondence to:
J Keeffe
Centre for Eye Research Australia, Department of Ophthalmology, The University of Melbourne, Australia; jillek@unimelb.edu.au
Childhood blindness is ranked second only to cataract on the global burden of eye disease
Keywords: childhood vision
While the number of children with vision loss and blindness is relatively low in comparison with the number of older people with vision loss, the impact as measured in disability adjusted life years (DALY) ranks childhood blindness second only to cataract on the global burden of eye disease and one of the five priority areas of the World Health Organization’s "Vision 2020—the right to sight" programme.1 Vision impairment, both low vision and blindness, compromises quality of life. Impaired vision from birth or in early childhood can have a profound impact on an infant’s or child’s development, restricting participation in social, physical and educational and, later, employment opportunities.
There is wide regional variation in the causes of vision loss and blindness. In both developed and developing countries, the majority of vision loss is either preventable or treatable.1 Cataract, retinal diseases, and congenital abnormalities are found in all regions. In developing or low income countries where much of the vision loss is related either to infection or nutrition, corneal scarring is the most common cause of blindness. The prevention of these conditions is largely at primary care level. In high and middle income countries where retinopathy of prematurity and lesions of the central nervous system are common, specialist paediatric ophthalmology services are needed for the prevention and particularly the management of vision loss in children.
The recent study of the incidence and causes of visual impairment and blindness in the United Kingdom found visual impairment was more common than expected and that it occurs in the context of non-ophthalmic impairments.2 Seventy eight per cent of the children diagnosed with uncorrectable vision loss in the United Kingdom over a 1 year period had impairments in addition to severe vision loss or blindness. The associated disorders were motor, sensory, or cognitive impairments or chronic serious disorders that affected development, education, or independent living. Infants and children with multiple impairments often require not only complex ophthalmic management but also multidisciplinary assessment and follow up, often over long periods of time.
A critical issue in health services research related to infants and children is that of timely, necessary, and appropriate referrals for early childhood intervention services. Follow up with parents can ascertain if referrals were accepted and acted on. Thus, in middle to high income countries such as the United Kingdom, health services research for children with impaired vision needs to include specialist paediatric ophthalmic services, other paediatric health care, habilitation, and education services. Evaluation of the effectiveness of the new community link team in the Great Ormond Street Hospital department of ophthalmology will provide useful information on the referrals and networking between the often large number of health, habilitation, and educational professionals involved with children with vision impairment, and especially those with multiple impairments.
The existence of bias in a study sample can lead to gaps in our knowledge of patterns of use of eye care and vision services
Health services information for adults is often included in population based studies of the prevalence and causes of eye disease in adults.3 There are few similar large scale population based studies of children. Those that have been conducted though4 do not help our understanding of the eye care services used by infants, children, and their families in countries such as the United Kingdom. It is clinic based surveys of families, such as that of Rahi and colleagues (p 782), which will provide much needed information.
A retrospective survey was sent to parents of children with newly diagnosed eye disease at a city hospital. To assess the barriers to participation and possible bias in health services research, the characteristics of participants were compared with those who did not participate. Sociodemographic data were extracted from hospital records, as was family history and degree of vision loss, non-ophthalmic disorders, and parents’ main language. The study found that those who were more likely to participate had no other vision impaired family members, were white British, spoke English as their main language, and were from higher socioeconomic groups.
Identification as a member of an ethnic group does not indicate the language spoken or the acculturation of the child or parents. Both the language spoken and cultural beliefs about vision impairment and disability are likely to affect a family’s experience and use of eye health services.
Most research is conducted only in the predominant community language, in this case English, thus possibly hindering participation by people who cannot read or speak English. The article discusses the difficulty of developing valid questionnaires in the languages required—it is not just a matter of translating the questions. The study group used one of its members, a Hindi speaker, to follow up people from south Asian countries. Based on their experience, they believe it might not be that the language spoken was a major barrier
Consideration of language spoken though is an important issue. A recent study in the United Kingdom found that the incidence of vision impairment was significantly higher in ethnic minorities than in "white" population. The odds of being vision impaired ranged from five times higher in south Asian groups, and over twice an elevated risk for "black" and other groups.
Cultural beliefs can influence a family’s reaction to and acceptance of a child with a disability. Blame for a vision disorder may be directed at one or both parents. Utilisation of traditional, alternative, or mainstream hospital and medical services can be related to practices in the country of birth of the parents. For this reason, representation of ethnic minorities in health service research is important to gain an understanding of services used.
One of the purposes of Rahi et al’s study was the experience of health services. A study in a mental health service related language spoken in patients’ country of birth to the length of time spent in clinic appointments.5 People from English speaking countries had significantly greater duration of face to face clinic visits than did people from countries where English is not the main language. Reasons for the difference in duration such as need for and availability of interpreters were not available in the data collected in that study. While in a different area of health, this issue is one that needs to be explored as ophthalmologists and hospitals are one of parents’ important sources of information about their child’s vision disorder.6
In another study of families of children at the same hospital, 25% of appointments were not kept during the study period. While there are no details of non-attendees, this again is likely to limit the scope of participants. The demographic details of the families such as socioeconomic groups were not reported. The cost of appointments is given as a reason for not attending appointments. This is the case even in public hospitals where there is no charge for the appointment. It is the cost of travel and foregone wages that preclude many people from attending apparently "free" appointments.
The study by Rahi and colleagues demonstrates the challenges of the inclusion of all potential groups of participants when conducting health services research in ethnically and socioeconomically diverse communities. The existence of bias in a study sample can lead to gaps in our knowledge of patterns of use of eye care and vision services.
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Gilbert C, Foster A. Childhood blindness in the context of Vision 2020—the right to sight. Bull World Health Organ 2001;79:227–32.
Rahi JS, Cable N. and the British Childhood Visual Impairment Study Group. Severe visual impairment and blindness in children in the UK. Lancet 2003;362:1359–65.
Keeffe JE, Weih LM, McCarty CA, et al. Utilisation of eye care services by urban and rural Australians. Br J Ophthalmol 2002;86:24–7.
Nirmalan PK, Vijayalakshmi P, Sheeladevi S, et al. The Kariapatti Pediatric Eye Evaluation Project: baseline ophthalmic data of children aged 15 years or younger in southern India. Am J Ophthalmol 2003;136:703–9.
Trauer T. Ethnic differences in the utilization of public psychiatric services in an area of suburban Melbourne. Aust NZ J Psychiatr 1995;29:615–23.
Rahi JS, Manaras I, Barr K. Information sources and their use by parents of children with ophthalmic disorders. Invest Ophthalmol Vis Sci 2003;44:2457–60.