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.