Consensus seems to be that they are not adequate for many patients.
Two recent media reports on online eye exams highlight the controversy over whether they are adequate to patient needs. The consensus among ODs and others interviewed by Healthline: The online tests are fast and cheap and therefore are, like most things that are fast and cheap, no substitute for the real thing. A New York Times contributor took one of the tests herself and pretty much agreed. “It’s not a comprehensive eye exam so it’s not a good option for people who have an unusual symptom or are worried about their eye health,” she writes, “including diseases such as glaucoma, cataracts and diabetes.”