Surgeons talk about a "look test" that refers to that certain something not captured by objective risk measures. A patient who doesn't look too bad on paper may look in person like they might not survive a haircut, let alone a valve replacement.

The database can store both objective and subjective risk measures. If there is good evidence that a 'look test' can improve risk assessment, lets get the referring doctor to perform a look test and store the result in the database. In that way the hospital will not have an edge over the risk-adjustment model used in the study.

Edit: Many patients are already assessed by performance status [1]

[1] https://en.wikipedia.org/wiki/Performance_status

Not the GP but I generally assume that a patient's actual doctors know more about that patient's physical body and how it will impact a procedure than some academics who are classifying/"coding" thousands of case files.