A group of doctors went bird sighting.
The general practitioner says: “Looks like a duck, swims like a duck, quacks like a duck, probably a duck”.
The psychiatrist spends two hour interviewing the duck and says: “This is a bird that thinks it’s a duck.”
The physician selects a stethoscope and after thoroughly examining the plumage, listening to the heart sounds of the bird, and consulting Harrison’s Textbook of Internal Medicine says: “This animal belongs to the Anatidae family of birds, which includes ducks, swans and geese. I will need to do some blood test and a chest x-ray to determine its exact subfamily.”
The surgeon takes out a gun, shoots the bird down, and hands the bird to the pathologist: “What is this?”
The pathologist spends a week dissecting the bird and examining the bird under the microscope. He then issues a 10 page report to the surgeon with the final paragraph saying
“Body of an adult bird, autopsy examination:
– Aylesbury Duck
– Gun shot wound through left ventricle of the heart
– Pulmonary aspergillosis
– Negative for malignancy”
And basically that’s what pathologists do. They examine specimens taken by clinicians and make detailed diagnoses on the specimen so that the referring clinician can tailor patient management appropriately…. Sometimes the diagnosis is too late, but it’s almost always correct.