Dhaliwal G. A piece of my mind. The mechanics of reasoning. JAMA. 2011 Sep. 7;306(9):918–919. PMID 21900128
Peterson MC, Holbrook JH, Hales Von D, Smith NL, Staker LV. Contributions of the history, physical examination, and laboratory investigation in making medical diagnoses. West J Med. 1992 Feb.;156(2):163–165. PMC1003190
These two papers are a brief and fascinating read on how we make diagnoses. The second one especially does some primary research on which part of our evaluation (history, exam and tests) help us the most.
Roughly 80% from the history is the rough ball park figure if you don’t want to go read it.
Now there are problems with the research as in all these studies as it seems that history always comes first so it always gets first stab at the diagnosis. I’m not sure how you’d do a study that did exam first as we need the history to guide the exam most of the time.
Still it’s nice to have some back up behind something that’s inherently obvious to anyone practicing medicine.