Myth: "An abnormal test result indicates you have a disease."
Truth: A test result outside the reference range (the normal range of test result) may or may not indicate a problem—it only indicates that your doctor should investigate it further. You can have an abnormal value and have nothing wrong—but your doctor should try to determine the cause.
About 5 to 8% of people have some of the test results outside the normal / reference range inspite of being healthy.
There are many other factors that can give a misleading result without indicating a major problem.
A high blood sugar could be diet-related rather than caused by diabetes. A lipid result could be high because you didn’t fast before the test.
At times the way sample is collected by the phlebotomist or the collection tubes that are used may be at fault and the sample collected may have some problem at the time of processing before the test is performed.
The lab tests are performed on instruments which have got their own sensitivity and they are electronic computers, just like any other electronic equipments or computers, there are certain number of errors or problems that may be the reason of the abnormal test results performed on that machine. Usually labs perform quality control procedures to prevent this sort of errors but no machines or procedures are 100% accurate all the time.
If your doctor is unsure about the test result they may wish to repeat it. Some abnormal results may disappear on their own, especially if they are on the border of the reference range.
So in case your lab test value is out of the normal or reference range indicated in the report, rather than being anxious or inferring that you are having some disease, the best option is to contact your doctor who can either repeat the test or perform some additional related tests which can either rule out or confirm whether you actually have the disease.