Visual Function after Correction of Distance Refractive Error with Ready-made and Custom Spectacles: A Randomized Clinical Trial
ABSTRACT To evaluate patient-reported outcome measures with the use of ready-made spectacles (RMS) and custom spectacles (CS) in an adult population in India with uncorrected refractive error (URE).
Prospective, double-masked, randomized trial with 1-month follow-up.
A total of 363 adults aged 18 to 45 years with ≥1 diopter (D) of URE (RMS, n = 183; CS, n = 180).
All participants received complete refraction and were randomized to receive CS (full sphero-cylindrical correction) or RMS based on the spherical equivalent for the eye with lower refractive error but limited to the powers in the RMS inventory.
Visual function and quality of life (VFQoL) instrument and participant satisfaction.
Rasch scores for VFQoL increased from 1.14 to 4.37 logits in the RMS group and from 1.11 to 4.72 logits in the CS group: respective mean changes of 3.23 (95% confidence interval [CI], 2.90-3.56) vs. 3.61 (95% CI, 3.34-3.88), respectively. Mean patient satisfaction also increased by 1.83 points (95% CI, 1.60-2.06) on a 5-point Likert scale in the RMS group and by 2.04 points (95% CI, 1.83-2.24) in the CS group. In bivariate analyses, CS was not associated with increased VFQoL or patient satisfaction compared with the RMS group. In the full multivariable linear regression, the CS group had greater improvement when compared with those receiving RMS (+0.45 logits; 95% CI, 0.02-0.88), and subjects with astigmatism >2.00 D had significantly less improvement (-0.99 logits; 95% CI, -1.68 to -0.30) after controlling for demographic and vision-related characteristics. In multivariable analysis, increased change in patient satisfaction was related to demographic and optical characteristics, but not spectacle group.
Ready-made spectacles produce large but slightly smaller improvements in VFQoL and similar satisfaction with vision at 1-month follow-up when compared with CS. Ready-made spectacles are suitable for the majority of individuals with URE in our study population, although those with high degrees of astigmatism may benefit from a trial of CS. This study provides further evidence for the use of RMS in settings where CS are unavailable or unaffordable, or refractive services are inaccessible to those in need.
The author(s) have no proprietary or commercial interest in any materials discussed in this article.
- [Show abstract] [Hide abstract]
ABSTRACT: PurposeGlobally, 153 million people are visually impaired from uncorrected refractive error. The aim of this research was to verify a method whereby autorefractors could be used by non-specialist health-workers to prescribe spectacles, which used a small stock of preformed lenses that fit frames with standardised apertures. These spectacles were named S-Glasses (Smart Glasses).Patients and methodsThis prospective, single-cohort exploratory study enrolled 53 patients with 94 eligible eyes having uncorrected vision of 6/18 or worse. Eyes with best-corrected vision worse than 6/12 were excluded. An autorefractor was used to obtain refractions, which were adjusted so that eyes with astigmatism less than 2.00 dioptres (D) received spherical equivalent lenses, and eyes with more astigmatism received toric lenses with a 2.50 D cylindrical element set at one of four meridians. The primary outcome was to compare S-Glasses vision with the WHO definition of visual impairment (6/18). Where astigmatism was 2.00 D or greater, comparison with spherical equivalent was made. Mixed-model analysis with repeated effect was used to account for possible correlation between the vision of fellow eyes of the same individual.ResultsS-Glasses corrected 100% of eyes with astigmatism less than 3.00 D and 69% of eyes with astigmatism of 3.00 D or greater. Spherical equivalent lenses corrected 25% of eyes with astigmatism of 2.00-2.99 D and 11% with astigmatism of at least 3.00 D.DiscussionS-Glasses could be beneficial to resource-poor populations without trained refractionists. This novel approach, using approximate toric lenses, results in superior vision for astigmatic patients compared with the practice of providing spherical equivalent alone.Eye advance online publication, 11 January 2013; doi:10.1038/eye.2012.286.Eye (London, England) 01/2013; 27(4). DOI:10.1038/eye.2012.286 · 1.90 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Uncorrected refractive error is the leading cause of global visual impairment. Given resource constraints in developing countries, the gold standard method of refractive error correction, custom-made spectacles, is unlikely to be available for some time. Therefore, ready-made and recycled spectacles are in wide use in the developing world. To ensure that refractive error interventions are successful, it is important that only appropriate modes of refractive error correction are used. As a basis for policy development, a systematic literature review was conducted of interventional studies analysing visual function, patient satisfaction and continued use outcomes of ready-made and recycled spectacles dispensed to individuals in developing countries with refractive errors or presbyopia. PubMed and CINAHL were searched by MESH terms and keywords related to ready-made and recycled spectacle interventions, yielding 185 non-duplicated papers. After applying exclusion criteria, eight papers describing seven studies of clinical outcomes of dispensing ready-made spectacles were retained for analysis. The two randomised controlled trials and five non-experimental studies suggest that ready-made spectacles can provide sufficient visual function for a large portion of the world's population with refractive error, including those with astigmatism and/or anisometropia. The follow-up period for many of the studies was too short to confidently comment on patient satisfaction and continued-use outcomes. No studies were found that met inclusion criteria and discussed recycled spectacles. The literature also notes concerns about quality and cost effectiveness of recycled spectacles, as well as their tendency to increase developing countries' reliance on outside sources of help. In light of the findings, the dispensing of ready-made spectacles should be favoured over the dispensing of recycled spectacles in developing countries.Clinical and Experimental Optometry 01/2014; 97(3). DOI:10.1111/cxo.12126 · 1.26 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Uncorrected refractive errors are the single largest cause of visual impairment globally. Refractive errors are an avoidable cause of visual impairment that are easily correctable. Provision of spectacles is a cost-effective measure. Unfortunately, this simple solution becomes a public health challenge in low- and middle-income countries because of the paucity of human resources for refraction and optical services, lack of access to refraction services in rural areas, and the cost of spectacles. Low-cost approaches to provide affordable glasses in developing countries are critical. A number of approaches has been tried to surmount the challenge, including ready-made spectacles, the use of focometers and self-adjustable glasses, among other modalities. Recently, self-adjustable spectacles have been validated in studies in both children and adults in developed and developing countries. A high degree of agreement between self-adjustable spectacles and cycloplegic subjective refraction has been reported. Self-refraction has also been found to be less prone to accommodative inaccuracy compared with non-cycloplegic autorefraction. The benefits of self-adjusted spectacles include: the potential for correction of both distance and near vision, applicability for all ages, the empowerment of lay workers, the increased participation of clients, augmented awareness of the mechanism of refraction, reduced costs of optical and refraction units in low-resource settings, and a relative reduction in costs for refraction services. Concerns requiring attention include a need for the improved cosmetic appearance of the currently available self-adjustable spectacles, an increased range of correction (currently -6 to +6 diopters), compliance with international standards, quality and affordability, and the likely impact on health systems. Self-adjustable spectacles show poor agreement with conventional refraction methods for high myopia and are unable to correct astigmatism. A limitation of the fluid-filled adjustable spectacles (AdSpecs, Adaptive Eyecare Ltd, Oxford, UK) is that once the spectacles are self-adjusted and the power fixed, they become unalterable, just like conventional spectacles. Therefore, they will need to be changed as refractive power changes over time. Current costs of adjustable spectacles are high in developing countries and therefore not affordable to a large segment of the population. Self-adjustable spectacles have potential for "upscaling" if some of the concerns raised are addressed satisfactorily.Clinical ophthalmology (Auckland, N.Z.) 02/2014; 8:405-413. DOI:10.2147/OPTH.S46057