Clinical outcomes following the dispensing of ready-made and recycled spectacles: a systematic literature review

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.

Keywords: public health; ready-made spectacles; recycled spectacles; refractive errors.