80% of diagnoses are made from the history. Every medical student is told this at some point. House mentions it a few times…
The history is the mainstay of your diagnostic process. Nobody knows your patient like the patient himself, where it hurst, whether it’s normal for him – ask! By the end of the history you should have an idea of the two or three things that it’s most likely to be.
You should only examine once you know what you’re looking for, to confirm the findings that you anticipate from the history. Equally you should only conduct further tests to confirm what you think you’ve found.