Some thoughts about the medical history

'Taking a history’ is one of the first clinical tasks medical students are taught. The logic behind this is inescapable: without the history, attempts at diagnosis and treatment are doomed to failure. We start our training with the history, when we present patients for discussion with other doctors (in training or later, in practice) we start with the history. And except in rare emergencies, we start every patient interaction with the history.  The history: it always starts there but it doesn’t end there.

What is it about the history that makes it so central and essential? I like to tell residents there are four ways the history makes everything else in medicine possible.

1. The first reason the history is important is so obvious that it is often the only value that people think about. The history is the most reliable way to learn about the symptoms or illness that the patient wants addressed. As such, it is absolutely necessary for diagnosis.  Ask any experienced clinician and they will tell you, the history is far and away our most important diagnostic tool. With it, we make a list of possibilities and then turn that list into a set of probabilities. Without the history, one doesn’t know what to focus one’s physical exam on,  what tests to order, or how to interpret the test results. I was taught: “If you don’t have the diagnosis on your list of possibilities at the end of the history, you will probably never make the diagnosis.” Sir William Osler captured this many years ago: “Listen to the patient. He is telling you the diagnosis.”
2. The history is also necessary - and the best way - to get information about the patient. The best clinicians do not treat diseases, they treat patients. Without knowing the patient and the patient’s context, there is a very real danger one will treat the disease and harm the patient. Osler nailed this one, also: “It is much more important to know what sort of patient has the disease than what sort of disease the patient has.”
3. The third reason the history is rightfully considered the cornerstone of clinical medicine is often forgotten: it is how the patient gets to know the clinician. Are we attentive? Are we respectful? Do we interrupt? Are we rushed? Do we care? Do we say so when we don’t know? Do we show interest in the whole patient, or only in their rash, gall bladder, or knee pain?  If we take a history properly, in addition to understanding the patient and their illness, we will have earned their trust. 
4. Finally, taking a history well involves the same skills necessary for building and maintaining long-term trusting relationships: listening, respect, tolerance, honesty, humility, communication, shared values. Taking the history well and collaboratively allows the patient and the clinician to learn to work together.