What is a differential diagnosis?

Question

are not all diagnoses differential?

Answer 1

It just means that a doctor/doctors will narrow down the probable condition to a few very likely variables rather than just one disease.

It's the initial diagnosis commonly used in medicine as it's dangerous to jump to conclusions - you need to make tests first based on what you think it could be, and only after the results, confirm one of the possibilities.

Answer 2

a differential diagnosis is a diagnosis which examines all of the possible causes for a set of symptoms in order to arrive at a diagnosis. For example, if a patient presents with a runny nose, doctors might consider causes like hay fever and colds in the differential diagnosis in an attempt to arrive at the right diagnosis. Many doctors use this system of diagnosis in their practices, and some doctors known as diagnosticians actually specialize in differential diagnosis. Fans of House, MD may be familiar with the mechanics of a differential diagnosis.

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