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 91 reviews. Three reviews covered more than one thematic area and were therefore included in the EGM more than once. 43 reviews address treatment of refractive error, 17 address the burden of disease (epidemiology) and 13 cover risk/prevention of refractive error. The remainder address screening (11), quality of life (five), quality of clinical care (four), quality of non-clinical care (two), and cost benefit (one).

This gap map shows that there are clear gaps in evidence at the health-systems sector level. No reviews were identified around access to health care services.

In response to the authors’ research questions, 58 reviews provide strong evidence, 20 reviews show weak or no evidence; and in 16 reviews the results are inconclusive (mixed results). The reviews were assessed for quality: 44 reviews are medium quality; 28 reviews are graded low quality; and 19 reviews are of high methodological quality.

Find out more about the key messages from this EGM in our Refractive error evidence brief.

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This evidence gap map was last updated in 2022.
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Sightsavers (2022). Refractive Error Evidence Gap Map [online] Available at: [Add date accessed]

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