Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Polycythemia Vera ?
    ### Response:
    Polycythemia vera (PV) may not cause signs or symptoms for years. The disease often is found during routine blood tests done for other reasons. If the results of your blood tests aren't normal, your doctor may want to do more tests.
                
Your doctor will diagnose PV based on your signs and symptoms, your age and overall health, your medical history, a physical exam, and test results.
    