This is where an objective parameter, such as a lab result, needs help from the "art of medicine".  What happens next depends a lot on the type of test.  If the lab result was truly unexpected and not consistent with the patient's overall picture then the test often gets repeated.  Machines make mistakes, people make mistakes, and so do labs.

What if the test result is correct but still falls outside of the normal range?  Sometimes that "normal range" must be put into context.  What is "normal" for an adult may not be normal for a child.

Were you taking medicine when the test was drawn?  This can sometimes affect blood test results, as can food or drink taken in prior to the test.  Some out-of-line laboratory numbers return to normal when blood is drawn after an overnight fast.

You already knew these things?  Perhaps you did, but there are patients is every physician's practice who seem panic-stricken when told that tests results are abnormal.  That's why an overall view which includes attention to the patient's age, sex, drugs, meal status and the potential for lab error must be considered when the test result falls outside the normal range.  For a copy of this script, access our web site, speakingofhealth.com.  Speaking of Health, I'm Dr. Steven Andrew Davis, for CBS News.