Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.
This work was supported by grants from the Swedish Research Council (#2011-3132), Swedish government (“Agreement concerning research and education of doctors”; ALF-GBG-145921), Göteborg Medical Society, the Knut and Alice Wallenberg Foundation, Marianne and Marcus Wallenberg Foundation, Dr Reinhard Marcuses Foundation, Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse, Hjalmar Svensson Foundation, Greta Andersson Foundation, Herman Svensson Foundation, Ögonfonden, De Blindas Vänner and Kronprinsessan Margaretas Arbetsnämnd för Synskadade.