Funding for this research was provided by:
Sight and Life Foundation (AWD-384984)
Text and Data Mining valid from 2018-12-01
Received: 4 April 2018
Accepted: 19 October 2018
First Online: 13 December 2018
Ethics approval and consent to participate
: This systematic review included the data from previously published studies. All data were already de-identified prior to analysis. This research was not considered human subjects research. No humans were consented to participate in the study and no approvals were sought from institutional review boards.
: Not applicable.
: The authors declare that they have no competing interests.
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