About the Authors

Anita Ramesh

Affiliation International Centre of Eye Health (ICEH), Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine (LSHTM), London, United Kingdom

Sari Kovats

sari.kovats@lshtm.ac.uk

Affiliation Department of Social and Environmental Health Research, Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine (LSHTM), London, United Kingdom

Dominic Haslam

Affiliation Sightsavers International, Haywards Heath, United Kingdom

Elena Schmidt

Affiliation Sightsavers International, Haywards Heath, United Kingdom

Clare E. Gilbert

Affiliation International Centre of Eye Health (ICEH), Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine (LSHTM), London, United Kingdom

Competing Interests

Authors Gilbert, Ramesh and Kovats declare no competing interest. Authors Schmidt and Haslam also declare no competing interests except to acknowledge that they are employees of Sightsavers who funded this systematic review. They were involved in the agreement of the review protocol, search strategy and interpretation of findings.

Author Contributions

Conceived and designed the experiments: AR CEG SK ES DH. Performed the experiments: AR. Analyzed the data: AR SK. Wrote the paper: AR SK CEG ES DH.