The impact of light source on discrimination ability in subjects with age-related macular degeneration

Visual impairment among Aboriginal and Torres Strait Islander patients attending an Australian Indigenous primary health service: a cross-sectional study

This cross-sectional study aimed to identify the period prevalence of visual impairment (VI) and blindness among Aboriginal and Torres Strait Islander people attending an Indigenous urban primary healthcare service, eye care practitioner referrals for those with VI and any opportunities to improve care delivery. Visual acuity (VA) examinations, using a Snellen chart, are performed as part of routine annual health assessments offered to children and adults. This study included patients aged ≥5 years (n=1442) who had a health assessment conducted between 1 January 2015 and 31 December 2016 and provided consent for the use of their health assessment information for research. Of patients with available data, 2.4% (33/1374) experienced VI, defined as presenting VA worse than 6/12 to 6/60 in the better-seeing eye. VI was more common in those aged ≥60 years (14/136; 10.3%) and was significantly associated with increasing age (P<0.001). No patients experienced blindness, defined as presenting VA worse than 6/60 in the better-seeing eye. All patients with VI were aged ≥16 years. Nine (27%) of the 33 patients with VI in the better-seeing eye were referred to an optometrist or an ophthalmologist. The low period prevalence of VI and no blindness in this study are positive findings. The findings also indicate that routine VA testing of older adults, especially those aged ≥60 years, should be conducted to avoid missing those not having an annual health assessment.

Lighting as a Compensatory Strategy for Acquired Visual Deficits After Stroke: Two Case Reports

OBJECTIVE. The objective of this article was to explore the effects of enhanced lighting on the function of people with an acquired visual deficit resulting from cerebrovascular accident (CVA) in an inpatient rehabilitation facility (IRF).

METHOD. An ABAB design was used with two cases to assess how a short-term intervention involving lighting changes affected clients’ grooming performance in an IRF. Analysis consisted of scores on the grooming section of the FIM®, times for each grooming task, and light meter readings.

RESULTS. Both participants demonstrated improvements in function as measured by the FIM and in time to complete grooming tasks with enhanced lighting.

CONCLUSION. These results suggest that individualized lighting can lead to improved grooming function in clients with CVA.

Measurement properties of continuous text reading performance tests

PURPOSE

Measurement properties of tests to assess reading acuity or reading performance have not been extensively evaluated. This study aims to provide an overview of the literature on available continuous text reading tests and their measurement properties.

METHODS

A literature search was performed in PubMed, Embase and PsycInfo. Subsequently, information on design and content of reading tests, study design and measurement properties were extracted using consensus-based standards for selection of health measurement instruments. Quality of studies, reading tests and measurement properties were systematically assessed using pre-specified criteria.

RESULTS

From 2334 identified articles, 20 relevant articles were found on measurement properties of three reading tests in various languages: IReST, MNread Reading Test and Radner Reading Charts. All three reading tests scored high on content validity. Reproducibility studies (repeated measurements between different testing sessions) of the IReST and MNread of commercially available reading tests in different languages were missing. The IReST scored best on inter-language comparison, the MNread scored well in repeatability studies (repeated measurements under the same conditions) and the Radner showed good reproducibility in studies.

CONCLUSIONS

Although in daily practice there are other continuous text reading tests available meeting the criteria of this review, measurement properties were described in scientific studies for only three of them. Of the few available studies, the quality and content of study design and methodology used varied. For testing existing reading tests and the development of new ones, for example in other languages, we make several recommendations, including careful description of patient characteristics, use of objective and subjective lighting levels, good control of working distance, documentation of the number of raters and their training, careful documentation of scoring rules and the use of Bland-Altman analyses or similar for reproducibility and repeatability studies.

Visual impairment as a function of visual acuity in both eyes and its impact on patient reported preferences

Purpose

To assess the impact of VA loss on patient reported utilities taking both eyes into account compared to taking only the better or the worse eye into account.

Methods

In this cross-sectional study 1085 patients and 254 controls rated preferences with the generic health-related (EQ-5D; n = 868) and vision-specific (Vision and Quality of Life Index (VisQoL); n = 837) multi-attribute utility instruments (MAUIs). Utilities were calculated for three levels of VA in the better and worse eyes, as well as for 6 different vision states based on combinations of the better and worse eye VA.

Results

Using the VisQoL, utility scores decreased significantly with deteriorating vision in both the better and worse eyes when analysed separately. When stratified by the 6 vision states, VisQoL utilities decreased as VA declined in the worse eye despite stable VA in the better eye. Differences in VisQoL scores were statistically significant for cases where the better eye had no vision impairment and the worse seeing fellow eye had mild, moderate or severe vision impairment. In contrast, the EQ-5D failed to capture changes in better or worse eye VA, or any of the six vision states.

Conclusions

Calculating utilities based only on better eye VA or using a generic MAUI is likely to underestimate the impact of vision impairment, particularly when the better eye has no or little VA loss and the worse eye is moderately to severely visually impaired. These findings have considerable implications for the assessment of overall visual impairment as well as economic evaluations within eye health.