PurposeTo determine the incremental cost‐effectiveness of portable electronic vision enhancement system (p‐EVES) devices compared with optical low vision aids (LVAs), for improving near vision visual function, quality of life and well‐being of people with a visual impairment.MethodsAn AB/BA randomized crossover trial design was used. Eighty‐two participants completed the study. Participants were current users of optical LVAs who had not tried a p‐EVES device before and had a stable visual impairment. The trial intervention was the addition of a p‐EVES device to the participant's existing optical LVA(s) for 2 months, and the control intervention was optical LVA use only, for 2 months. Cost‐effectiveness and cost‐utility analyses were conducted from a societal perspective.ResultsThe mean cost of the p‐EVES intervention was £448. Carer costs were £30 (4.46 hr) less for the p‐EVES intervention compared with the LVA only control. The mean difference in total costs was £417. Bootstrapping gave an incremental cost‐effectiveness ratio (ICER) of £736 (95% CI £481 to £1525) for a 7% improvement in near vision visual function. Cost per quality‐adjusted life year (QALY) ranged from £56 991 (lower 95% CI = £19 801) to £66 490 (lower 95% CI = £23 055). Sensitivity analysis varying the commercial price of the p‐EVES device reduced ICERs by up to 75%, with cost per QALYs falling below £30 000.ConclusionPortable electronic vision enhancement system (p‐EVES) devices are likely to be a cost‐effective use of healthcare resources for improving near vision visual function, but this does not translate into cost‐effective improvements in quality of life, capability or well‐being.

This study investigates whether systematic differences exist between the accommodation response/stimulus curves of emmetropes and myopes when the targets are sinusoidal gratings, in particular whether myopic accommodation is relatively less effective when presented with targets of high spatial frequency due to increased tolerance to defocus blur. Ten emmetropes (overall mean sphere +0.19 D, range -0.37 to +1.37 D) and 10 myopes (overall mean sphere -2.89 D, range -1.13 to -6.63 D) viewed Gabor targets with dominant frequencies 1, 4, 8 and 16 c/deg. Maximal grating contrast was 80% and the full, green, stimulus field was 6 deg. Subjects were aged between 18 and 37 years. A further high-contrast 6/30 optotype target was included for comparison purposes. Viewing was monocular, the other eye being occluded. Stimulus demand was varied with trial lenses over the nominal range 0 to 6.0 D and the corresponding accommodation responses were recorded with an open-view, Shin-Nippon SRW-5000 auto-refractor. The resulting accommodation response/stimulus curves were characterized by their slopes over the stimulus range 1.5 to 6.0 D and by an "error index" indicating the extent to which the responses differed from the ideal 1:1 response/stimulus line. No significant differences were found between the mean accommodative behavior of the two refractive groups for any target. There were, however, substantial inter-subject differences. Some subjects in both groups showed more accurate responses with the higher spatial-frequency targets, while others showed optimal response at intermediate frequencies. Although it has been reported in the literature that, in comparison to emmetropes, myopes have reduced sensitivity to blur and response/stimulus curves of lower slope, the present study failed to demonstrate any reduction in their responses to gratings of relatively high spatial frequency. For each target the two refractive groups showed similar accommodative behavior.

The study provides evidence that p-EVES devices can play a useful role in supplementing the range of low vision aids used to reduce activity limitation for near vision tasks.

The evidence base in low vision rehabilitation is modest and further high quality clinical trials are required to inform decisions on healthcare provision. The p-EVES study findings are anticipated to contribute to this broader evidence requirement, with the methodological issues evident here being relevant to other trials within the field.