in a metropolitan city four hours away, it's that there isn't a retina specialist at your grocery store. And CNNs could facilitate the integration of diabetic retinopathy and other screening programs into primary care. But before that happens, more research, especially prospective clinical trials, are needed. The way we do approach these things is really the way that medicine usually works, which is to say, "let's do validations of the method again and again and again until we're sure, we're reasonably confident that it really works on many kinds of images,