> There are so many confounding variables that even trying to measure outcomes 90 days out is difficult.
Very much this. Two patients, same doctor, same proceedure, with somewhat similar medical backgrounds. Nearly the same progression in the hospital, and released to go home, and possibly to doctors that don't interact with that hospital.
Perhaps one is poor and sometimes skips medication. Only one starts eating healthily and starts exercise. One has a stressful home life. Maybe one, when the recovery isn't going as quickly as possible, starts mixing in alternative medicines but doesn't tell his GP. Maybe they were both women, in the hospital to give birth - and one got pregnant again in the first year while the other didn't. These sorts of things greatly affect the outcomes, but none of them are under the hospital's controls.
Very much this. Two patients, same doctor, same proceedure, with somewhat similar medical backgrounds. Nearly the same progression in the hospital, and released to go home, and possibly to doctors that don't interact with that hospital.
Perhaps one is poor and sometimes skips medication. Only one starts eating healthily and starts exercise. One has a stressful home life. Maybe one, when the recovery isn't going as quickly as possible, starts mixing in alternative medicines but doesn't tell his GP. Maybe they were both women, in the hospital to give birth - and one got pregnant again in the first year while the other didn't. These sorts of things greatly affect the outcomes, but none of them are under the hospital's controls.