How do doctors make predictions of how long someone will live or if they’ll ever walk normally again?

Question

I was rewatching an old video on YouTube and the guy was able to walk again after 10 months of practicing yoga and losing 140 lbs. If no one on earth can exactly predict when someone will die or if they’ll be able to walk again, how and why do doctors come up with these predictions?

https://youtu.be/qX9FSZJu448

In: Mathematics

Answer 1

Doctor here:

You can’t really do this, except on a handful of diagnosis, there are big studies that compare outcomes based on factors that the patients have, age, weight, etc, and in cancer we use the type of cancer as well as the stage of it (how bad has it gone).

These studies tell you roughly how much people who have certain characteristics live with a diagnosis, I personally don’t like to do predictions but I’ve met oncologist who actually do them very accurately.

There is a great debate on whether predicting mortality is ethical or not.