Refractive error evidence gap map

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What this map shows

At Sightsavers, our EGMs summarise, appraise, and present evidence from systematic or literature reviews.

The refractive error gap map summarises evidence from 29 reviews. Two reviews covered more than one thematic area and were therefore included in the EGM more than once. 11 reviews address case detection/screening and 11 address treatment of refractive error. The remainder address quality of clinical care (three), epidemiology (two), quality of life (two), risk factors (one) and cost benefit analysis (one).

This gap map shows that there are clear gaps in evidence at the health-systems sector level. No reviews were identified around the quality of non-clinical care for refractive error, and access to health care services.

In response to the authors’ research questions, 13 reviews provide strong evidence, 12 reviews show weak or no evidence; and in six reviews the results are inconclusive (mixed results). The reviews were assessed for quality: 11 reviews are of high methodological quality; 10 reviews are medium quality; and 10 reviews are graded low quality.

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This evidence gap map was last updated in 2015.
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Sightsavers (2015). Refractive Error Evidence Gap Map [online] Available at: [Add date accessed]

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