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

Others have said it, but the simplest answer is statistics. If 90% of people at the current state patient is in die within a year, they can inform the patient that. It doesnt mean the patient will certainly be dead in a year, but theres a high likelihood of that.