Bruce J. W. Evans

Correctable visual impairment in older people: a major unmet need

This review seeks to determine the prevalence of correctable visual impairment (VI) in older people in the UK, to discover what proportion of these cases are undetected, to suggest reasons for the poor detection and to make recommendations for improving the detection. To establish the context of these issues, the review will also touch on the general prevalence and causes of VI in older people in developed countries and on the impact of VI in older people. Typically, studies suggest that VI affects about 10% of people aged 65–75, and 20% of those aged 75 or older. There is a strong relationship between impaired vision in older people and both reduced quality of life and increased risk of accidents, particularly falls. The literature suggests that those with low vision are about two times more likely to have falls than fully sighted people, and the annual UK cost of treating falls directly attributable to VI is £128u2003million. The literature on the prevalence of undetected reduced vision in older people reveals that between 20 and 50% of older people have undetected reduced vision. The majority of these people have correctable visual problems (refractive errors or cataract). It is particularly startling that, in ‘developed countries’, between 7 and 34% of older people have VI that could simply be cured by appropriate spectacles. The reasons why so many cases of treatable VI remain untreated are discussed, and suggestions are made for improving the detection of these cases. We conclude that there should be better publicity encouraging older people to attend for regular optometric eye examinations. A complementary approach is annual visual screening of the elderly, possibly as part of GPs annual health check on people aged 75u2003years and older. Recommendations are made for evaluating new approaches to screening and for improving the management of cases detected by screening.

Susceptibility to Visual Discomfort of 3-D Displays by Visual Performance Measures

People with some signs of binocular dysfunctioning can be susceptible to visual complaints associated with viewing stereoscopic content at large viewing distances. Two performance measurements enabled to distinguish people by their binocular status (BS) in previous research: the ratio of performance of the Wilkins rate of reading test (WRRT) between 2-D and 3-D, and the vergence facility. In an experiment, first, an extensive optometric screening was carried out to differentiate visually asymptomatic young adults with good BS (GBS) (N = 27) from those with a moderate BS (MBS) (N = 6). Second, participants had to perform the WRRT at short viewing distance followed by a questionnaire under different screen disparity settings. The results reveal that the ratio of the WRRT between 0 and -1.5 screen disparity is an appropriate indicator of participants with MBS in comparison with participants with GBS. In addition, the results show that 0.75° of screen disparity is already problematic for people with MBS. We conclude that the WRRT-ratio has potential as a BS test in consumer applications to provide individual settings for comfortable screen disparities based on viewers BS.

Measuring clinical practice

The goals of this paper are to review techniques for measuring clinical practice within healthcare professions and to discuss possible applications of these techniques to primary care optometry. A review of the literature suggests a lack of systematic research investigating standards of clinical practice within optometry. It is argued that evidence‐based research to determine the content of typical optometric eye examinations would be valuable for several reasons: to evaluate the service provided to the public by the profession; setting priorities and assessing the outcomes of continuous education and training; to influence governmental and professional policy decisions; National Health Service General Ophthalmic Services issues; the equitable management of clinicolegal matters and consumer complaints; setting appropriate professional guidelines and developing undergraduate training. Evidence‐based studies within other healthcare professions have evaluated the content of clinical consultations. The literature reviewed reveals three main approaches: (1) abstraction of medical records, (2) use of clinical vignettes and (3) use of standardized patients (SPs) who present unannounced to clinics. In this review, we compare and contrast the use of these different methods in assessing the content of clinical consultations. It is clear from the literature reviewed that the use of SPs is the ‘gold standard’ methodology. Clinical vignettes can also provide useful data, especially if computerized.

A comparison of standardised patients, record abstraction and clinical vignettes for the purpose of measuring clinical practice

Background:u2002 A recent review found standardised patient (SP) methodology to be the gold standard method for evaluating clinical care. Alternative methods include record abstraction and computerised clinical vignettes. SPs were compared to clinical records and to computerised vignettes in order to assess whether record abstraction and vignettes are accurate measures of clinical care provided within optometry.

Glaucoma detection: the content of optometric eye examinations for a presbyopic patient of African racial descent.

Aims: Standardised patient (SP) methodology is the gold standard for evaluating clinical practice. We investigated the content of optometric eyecare for an early presbyopic SP of African racial descent, an “at-risk” patient group for primary open-angle glaucoma (POAG). Methods: A trained actor presented unannounced as a 44-year-old patient of African racial descent, complaining of recent near vision difficulties, to 100 community optometrists for an audio-recorded eye examination. The eye examinations were subsequently assessed via a checklist based on evidence-based POAG reviews, clinical guidelines and expert panel opinion. Results: Ninety-five per cent of optometrists carried out optic disc assessment and tonometry, which conforms to the UK College of Optometrists’ advice that those patients aged >40 years should receive at least two of the following tests: tonometry, optic disc assessment, visual field testing. Thirty-five per cent of optometrists carried out all of these tests and 6% advised the SP of increased POAG risk in those of African racial descent. Conclusion: SP encounters are an effective measure of optometric clinical practice. As in other healthcare disciplines, there are substantial differences between optometrists in the depth of their clinical investigations, challenging the concept of a “standard sight test”. There is a need for continuing professional development (CPD) in glaucoma screening, in which the increased risk of POAG in those of African racial descent should be emphasised.

An investigation of the optometric correlates of reading disability

The optometric correlates of dyslexia are reviewed. A small study is described that aimed to explore the ophthalmic correlates of reading disability and identify the most appropriate tests for further investigation. Full psychometric data were available for the subjects, most of whom had varying degrees of reading disability. A comprehensive optometric examination was carried out, including several tests of oculomotor performance, two versions of the Dunlop Test, and a test of pattern glare. Certain optometric variables were found to be significandy correlated with the degree of reading retardation, most notably the convergence and accommodative amplitudes. These results were still significant when the effects of intelligence and age were partialled out. Although the sample size limits the interpretation of these findings, several areas and optometric techniques for further investigation were identified.

Manufacturer changes lead to clinically important differences between two editions of the TNO stereotest

Stereoacuity tests used in clinical practice should be repeatable and reproducible. However, it has been observed in a clinical setting that new editions of the TNO stereotest appear to give different values from those obtained using previous versions. The purpose of the present research was to investigate this observation.

The content of optometric eye examinations for a young myope with headaches

Background:u2002 A recent review found standardised patient (SP) methodology to be the gold standard methodology for evaluating clinical care. We used this to investigate the content of optometric eye care for a young myopic patient with headaches suggestive of migraine.

A survey of the availability of state-funded primary eye care in the UK for the very young and very old

Background:u2002 The National Health Service (NHS) provides General Ophthalmic Services (GOS) to eligible patients in the UK. Nearly all community optical practices have a contract with the NHS via local primary care organisations (primary care trusts in England) allowing the practices to provide NHS sight tests to eligible patients.

The content of optometric eye examinations for a presbyopic patient presenting with symptoms of flashing lights

Background:u2002 Standardised patients (SPs) are the gold standard methodology for evaluating clinical care. This approach was used to investigate the content of optometric eyecare for a presbyopic patient who presented with recent photopsia.