Medical Test Results: Are You Normal, and Is That a Good Thing? - What Your Doctor Is Saying - Harvard Commentaries

When doctors talk shop, they often use terms to describe an examination or test result by comparing it to "normal." While this might seem straightforward, health care professionals use several expressions that might confuse you if you aren't prepared. Read on to learn how to interpret what your doctor is saying when he or she sends you a note, calls you or talks with you in the office about the results of your evaluation.

Fortunately, in the majority of doctors' practices, the most frequent result of an examination or testing is "normal."

I recall having a throat culture performed at the college infirmary; when I stopped by to get the results, the physician simply pointed to the actual report from the laboratory: It read "Negative" in bold letters. That worried me, because I thought that "negative" meant something bad and that a positive result was a good thing.

In fact, when reading medical results, it's usually the opposite; with rare exception, "negative" is normal (because it means that an abnormal result is not present) and "positive" is abnormal or unusual (because it means that something out of the ordinary is present).

There are several ways health care professionals express normalcy. These include:

Within normal limits ("wnl") — Many test results have cutoffs above which the result is too high and below which the result is too low. Usually, these cutoffs are established by measuring the test in normal, healthy people (called "a reference group") and figuring out where 95% of the results fall; if your result falls in between the cutoffs, your health care professional may call it "wnl," "in the normal range" or "within the reference range."

Unremarkable — An unremarkable result means that it is much like other, normal results. Generally, that's a good situation. It's usually good not to be too "interesting" when it comes to your health, so hearing that your result is unremarkable should not be taken to mean that your doctor is not interested or impressed with you!

Unimpressive — As above, this term implies that if there is any abnormality detected, it is minimal or insignificant.

Nonfocal, or, no focal abnormalities — These terms rely on the finding that in the human body, there is often symmetry between the right and left sides and there is uniformity in the makeup of many organs. If there is a "focal" finding, it indicates a localized abnormality where none should exist. Examples include a difference in the knee reflexes, or a spot on a chest X-ray where usually the lung appears uniform. "Nonfocal" findings usually indicate the absence of such an abnormality.

Intact — This is used to indicate that something that should be present is in fact present. Examples include pulses or reflexes.

Non-pathologic, benign — Some serious abnormalities have features that distinguish them from unimportant ones. For example, lymph nodes may enlarge to a certain point in healthy people, but above a certain size could indicate cancer or other problems. If a CT scan reveals slightly enlarged lymph nodes that otherwise appear normal, the report may describe them as "benign-appearing" or "non-pathologic," indicating the high likelihood that they are not an indicator of cancer or other serious illness.

Insignificant — This term is often used in the usual way, to describe a finding that may be minimally abnormal or abnormal in an unimportant way (for example, as a freckle on the skin). Another way this term is used is as a statistical measure regarding the likelihood that an abnormal finding is "truly abnormal" or "abnormal due to chance." When the findings are mathematically estimated to occur just as a matter of chance, the results may be termed "insignificant."

Stable — This indicates that the result is similar to previous findings; while it may not technically be normal, if it is not changing over time, at least the abnormality is not worsening. Such a finding generally provides some measure of reassurance.

Frequently, when the results of an examination or a test are not normal, the abnormality is minor and has little or no bearing on your health. So, health care professionals have several ways to express a result that is not normal, but often provide descriptive detail to specify just how abnormal or concerning it is.

For some tests, such as blood counts, the result is high, low or normal. For others, such as an X-ray, results may show an abnormality of little importance, such as a speck of calcium in the lungs or scarring from past pneumonia. It is not rare that the importance of an abnormality is not known right away and that more testing or the passage of time is needed to know for sure how meaningful it is. Examples of ways an abnormal examination or test results might be expressed by a health care professional include:

Elevated/increased/high — For example, the white-blood-cell count may be elevated in people with infection.

Depressed/decreased/low — For example, anemia is defined by having a reduced number of red blood cells. Blood pressure and hormone levels are other common examples of results that are typically expressed as high, low or normal.

Minimal, mild, moderate, marked, severe — Any abnormality may be described in terms of how abnormal it is. For example, X-rays may indicate mild arthritis even in people without symptoms; such findings are common in people over age 50 even if the joints feel fine. However, severe joint disease on an X-ray is less commonly seen in people whose joints feel fine, so the severity of the abnormality on an X-ray is typically described by radiologists in these terms.

Uncertain significance — Because tests have not been evaluated in every conceivable situation, their results may be abnormal but the importance of the finding is not completely understood. A good example of this type of finding is the magnetic resonance imaging (MRI) test. When MRIs first became available, spots commonly were observed in the brains of normal people (in fact, they were often referred to as "unidentified bright objects" or UBOs, because they appeared lighter than normal brain tissue). Such findings are common for many tests, particularly those that display images of the body.

There are times when a result that is out of the normal range is a good thing and what is usually considered "normal" is bad. For example, if you are taking the blood thinner warfarin (Coumadin), the test that measures blood clotting, (called the International Normalized Ratio, or INR) should be elevated; it indicates that clotting of the blood is less likely, a good thing for people who have had problems with blood clots. Getting the blood "thinner" and less likely to clot is the reason people take warfarin. While the urgency depends on the reason you are taking warfarin, a normal result is not a good result; it indicates that the medication is not thinning the blood enough. Another example is a pregnancy test; if you are trying to become pregnant, a "positive" result (indicating that you are pregnant) is a good thing and a negative result may be cause for disappointment.

A key part of understanding one's test results is knowing what the test is supposed to do. When I learned that my throat culture was "negative," that only meant I was less likely to have strep throat. There was still a small chance I had strep infection (because the test isn't perfect), and I could still have another cause of a sore throat, such as a viral infection or even a bacterial infection other than strep. The test did not mean I was healthy; it could only help to make one diagnosis (strep throat) more or less likely. Asking your doctor about the purpose of your tests may help you to understand their results.

Robert H. Shmerling, M.D., is associate physician at Beth Israel Deaconess Medical Center and associate professor at Harvard Medical School. He has been a practicing rheumatologist for over 20 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program.