These visual impairment evidence gap-maps (EGMs) have been developed by a team of researchers from Sightsavers, the Cochrane Eyes and Vision Group and the International Centre for Eye Health at the London School of Hygiene and Tropical Medicine, drawing on the guidance and previous experiences of the International Initiative for Impact Evaluation (3ie), which initiated the development of EGMs.
The development of EGMs followed a standardised systematic process:
EGMs were produced by constructing matrices, where review focus areas are displayed along the x axis, and the strength of evidence is shown along the y axis. The bubbles in the matrix cells represent each systematic or literature review. Clicking on a bubble will open up a summary page.
The cells where no reviews are shown indicate the areas where more evidence is required and where future research efforts should be directed.
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