Hi, this is Dr Sathya. Thanks for your question and I am very glad to help you.
The expression "Clinical correlation is recommended" is used during the reporting of a laboratory investigation like x ray, CT/MRI, blood tests or for that matter any tests/investigations.
This expression is added to the report because the Dr who interprets the x ray or other test report sees a finding on the test that has more than one possibilities. The reporting Dr is not familiar with the patient's clinical history & examination findings so they let the patient's clinic Dr make the final decision regarding out of the many different possibilities which is the most likely possibility.
I will try to give an example; let us say on the x ray of the bone there was a lesion (abnormal area) and that can be produced by many different possibilities like a fracture, infection, and other kinds of bone pathologies. Since the radiology Dr who reads the x ray has no full history of the patient they will write the different possibilities mentioned above in the report and let the patient's clinic Dr to finalize the diagnosis. In the same example mentioned above let us say patient's clinic Dr knows that the patient had a history of bone fracture then that will be the final diagnosis (the remaining possibilities are automatically ruled out during the clinical correlation).
So basically the above expression is used by reporting Drs who write the test findings - where there are more than one possibility for the same finding and since the reporting Dr does not have all the details of the patient they let the patient's clinic Dr to finalize the diagnosis so in the report they use the expression "further clinical correlation is recommended" or just "clinical correlation is recommended" etc.
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