In 2016, Geoff Hinton, one of the world's leading A.I. researchers, argued the technology would eclipse the skills of a radiologist within five years. "I think that if you work as a radiologist, you are like Wile E. Coyote in the cartoon," he told The New Yorker in 2017. "You're already over the edge of the cliff, but you haven't yet looked down. Mr. Hinton and two of his students at the University of Toronto built an image recognition system that could accurately identify common objects like flowers, dogs and cars. The technology at the heart of their system -- called a neural network -- is modeled on how the human brain processes information from different sources.

Dr. John Walker: Number one and two are kidney disease and medications. The kidney disease was unexpected. When you get your blood drawn and get it back from the lab, there are a couple of numbers in there called creatinine and GFR. They're wrong because your kidney health is related to your age and gender, and this creatinine level, but also your body: your height and weight. Since no blood lab ever asks you for your height and weight, they just make a best guess.