Funding for this research was provided by:
National Eye Institute (NIH-NEI EY017001)
Received: 19 February 2020
Accepted: 11 June 2020
First Online: 29 July 2020
Ethics approval and consent to participate
: All observers gave informed consent and were paid at a rate of US$11/h. For all experiments in this study, informed consent procedures were approved by the Partners Human Research Committee, protocol 2007P000646/BWH.
: Not applicable
: An author of this paper is Editor-in-Chief of the Journal. Peer review of this paper was handled by Associate Editors of the Journal. The Editor-in-Chief was not involved during peer review, except as necessary in an author role.