Cognitive Dissonance | "Sometimes people hold a core belief that is very strong. When they are presented with evidence that works against that belief, the new evidence cannot be accepted. It would create a feeling that is extremely uncomfortable, called cognitive dissonance. And because it is so important to protect the core belief, they will rationalize, ignore and even deny anything that doesn't fit in with the core belief." --Frantz Fanon
Being aware of these things could greatly increase doctor-patient relationship. If a doctor is more personable, the patient will be more willing to listen to them. If the doctor has higher expectations of the patient (either in the procedure being done or recovery time) the patient will do better and try to meet those expectations. It's simple psychology, really.