Funding for this research was provided by:
Deutsche Gesellschaft für Internationale Zusammenarbeit (DeveloPPP)
Received: 10 January 2019
Accepted: 22 October 2019
First Online: 16 December 2019
Ethics approval and consent to participate
: All study activities were approved by the Ethical Review Committee of the London School of Hygiene and Tropical Medicine (13914), the Asian Eye Institute Ethics Review Committee and Tropical Disease Foundation in the Philippines. Oral informed assent was recorded prior to interviews or surveys with children and written informed consent collected from parents and care takers and all adults involved in the study. Assent and consent procedures were approved by all relevant ethical review bodies. The trial was registered at ExternalRef removed, reference: NCT03204175.
: Not applicable
: The authors declare that they have no competing interests.