The extended role of the new school doctor

The assessment and management of strabismus and amblyopia: a national audit

AIMS

To determine what systems are in place within ophthalmic services for the assessment and management of children suspected of having amblyopia and strabismus. To find out what methods are used for the assessment of these children.

METHODS

A questionnaire-based study auditing 288 orthoptic departments in the UK.

RESULTS

Responses were received from 75% orthoptic departments. Most hospitals employ more than one system for the assessment of strabismus and amblyopia, which is generally dependent on route of referral. These include 'orthoptic assessment without refraction' (66%), 'combined orthoptist and ophthalmologist assessment' (66%), while 22% have an entirely orthoptist/optometric system. Ophthalmologists are involved in the initial assessment in 145 units (67%), whereas some units involve an ophthalmologist only if response to treatment is poor (15%), or if surgery is required (6%). Fourteen per cent of units reviewed all children, with discharge criteria being based on normal visual acuity (52%), accurate visual acuity (39%) and a normal orthoptic assessment (42%). Seventy-six per cent of units review some children, commonly as a result of family history (55%), parental concern (43%), poor co-operation (30%) and young age (72%). In the absence of squint or amblyopia children are discharged at the first visit, in only 8% of units. There is considerable variation in the tests used to assess visual acuity. LogMAR-based tests (eg EDTRS) are not routinely used in 75% of units.

CONCLUSION

Different systems exist for the assessment and management of squint and amblyopia across the country. While much of this variation is to be expected given their possible aetiologies, some could be reduced to produce a more cohesive service. There is also considerable scope for rationalising the tests used to screen infants and children for amblyopia and strabismus.

Screening for amblyopia in preschool children: results of a population-based, randomised controlled trial. ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood

INTRODUCTION

The rationale for preschool vision screening programmes has recently been questioned. Evidence about the effects of early treatment is needed, but it is not known how early the target conditions can reliably be detected. In this study, an intensive programme comprising several different screening methods, used at different ages up to 37 months, was compared with the usual practice of visual surveillance and ad hoc referrals.

METHODS

Two groups were randomly selected from children in a population birth cohort study. The control group (n = 1461) received visual surveillance only. The intervention group (n = 2029) was offered in addition a programme of regular visual assessments by orthoptists testing visual acuity, ocular alignment, stereopsis and non-cycloplegic photorefraction.

RESULTS

The intervention group programme yielded more children with amblyopia (1.6% vs. 0.5%, p < 0.01), and was more specific (95% vs. 92%, p < 0.01), than the control programme. The individual components of the intervention programme were compared. The cover test and visual acuity tests were poorly sensitive until the children were 37 months, but were always >99% specific. Photorefraction was more sensitive than acuity testing at all ages below 37 months, with specificity >95% at 31 and 37 months.

CONCLUSIONS

Photorefraction would have detected more children less than 37 months of age with straight-eyed amblyopia than did visual acuity testing, but with more false positives. At 37 months, photorefraction plus a cover test would have been comparable in effectiveness to visual acuity testing plus a cover test.

Economics, public health and health care purchasing: the Tayside experience of programme budgeting and marginal analysis

In this paper it is shown how the economics framework of programme budgeting and marginal analysis (PBMA) can be used to help formulate a purchasing strategy in health care; in this case, for child health services. The basic premise of PBMA is that to have more of some services it is necessary to have less of others. Therefore, it is important to know how resources are currently spent, what changes can be made, and what are the possible costs and benefits of such changes. Despite a lack of evidence on the effectiveness of services, PBMA provides a pragmatic purchasing framework. This framework permits consideration of national policy, local epidemiology, current spending, and the views both of parents and professionals as to how such spending can be changed.