Funding for this research was provided by:
International Glaucoma Association
Article History
Received: 7 July 2017
Accepted: 22 June 2018
First Online: 3 July 2018
Ethics approval and consent to participate
: The ethics reference number was 12/NW/0259 (North West Research Ethics committee, Lancaster). Informed written consent was taken from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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