Understanding your laboratory test results

We all face medical tests even in routine medical examinations. Often it becomes essential to have more information about a patient's condition than a simple physical examination. But the end of it you get a piece of paper reporting numbers as your test result and a line saying results are outside the range. You start to panick, "I am seriously ill". Is that true?

Test result

There are two types of test results. Some tests have yes or a no result. For example, you have infection or you do not have it. There is no in between and such results are easy to understand. . However, results such as blood cell count, or sugar level, or blood pressure, all come with a numeric value. This value may be a range as well. How do you know whether your blood sugar level is too high or too low? You compare with a reference range.

The reference range

The reference range signifies that most healthy people have a value for that test somewhere in between that range. Such a reference range is established by statistical observation on thousands of people. Such ranges are established with experience and observation.

What does it mean out of range?

One single test result outside the reference range actually means nothing other than more tests are required to be done. Such results indicate an abnormality but do not, or rather cannot, establish you are unwell. Test results are often influenced by the context and your physical constitution.

What affects results?

There are many factors that affect your results: sex, age, race, physical fitness, other underlying diseases, and the medication you are currently prescribed, or even past medical history. This is why it is very important to maintain medical history very carefully. Your medical history may help to establish a reference range for you which will be far more accurate than existing statistical references.

Things to note:

• It is a misconception that an abnormal test result is a sign of a serious problem.
• If test results are normal it is a good sign, but a single group of tests is often not enough to establish a condition either.

Compiled by: Indrajit Sinha; Last updated: 19.11.07© Medhospital Foundation

There is no generalization possible in medicine. The pages included in this website are purely educational and have been presented for information purpose only. Each section has been prepared with utmost care but should not be used as a substitute for your own physician's advice and care. Please see conditions for use.