How to Understand Your Lab Results

A laboratory (lab) test checks a sample of your blood, urine (pee), or other body fluid or tissue to learn about your health. The sample is sent to a lab where health care professionals test it to see if it contains certain substances and, if so, how much. Some lab tests can clearly show whether you do or don't have a specific health condition.

For example, a pregnancy test can show whether or not you are pregnant. Other lab tests provide more general information about your health and possible problems. A comprehensive metabolic panel (CMP), for example, can give your health care provider a good idea of your overall physical health.

Any abnormal results in these kinds of general lab tests can give your provider clues about the type of health problems you may have. Though lab tests are an important part of your health care, they don't provide a complete picture of your health. To get a full picture, your provider will use your results along with: Information from your physical exam.; Your health history.; Your family health history.; Any imaging tests you may have had, such as x-rays.; In most cases, combining that information leads to a more accurate diagnosis than the results from any one lab test.

So, even if you get your test results in your electronic health record (EHR) and can review them, it's still important to talk with your provider to find out what your results really mean for you.

Why this test is done

Your provider may order a lab test to:

• Learn more about a specific part of your health.
• Get a general picture of your overall health.

If your provider orders a test to learn more about a specific part of your health, they can use the results to:

• Diagnose or rule out a certain disease or condition, especially if you have symptoms. For example, if you're sick with a sore throat, swollen tonsils, and a fever, a strep A test can show you whether you're infected with the bacteria that causes strep throat.
• Monitor a condition and/or disease. Test results can help your provider see if your condition is getting better, worse, or staying the same. They can also tell your provider if your treatment is working. For example, a blood glucose test is often used to monitor diabetes and diabetes treatment.
• Determine the best treatment option for you. Certain tests can give your provider detailed information about your health condition. Your provider can then use the results of these tests to figure out which treatment will be effective. Tumor marker tests, for example, can help your provider decide how best to treat certain types of cancer.

Lab tests that provide a more general picture of your health are often used even if you don't have any signs or symptoms of a health condition. These tests are usually part of a routine checkup and can tell your provider if you:

• Are at high risk for a specific disease. For example, a cholesterol test measures the amount of cholesterol in a sample of your blood. The results can help you understand your risk for heart disease.
• Need additional testing. These tests look for signs that you may have a health problem so that you can have more testing to find out for sure. For example, one type of test for colon cancer looks for blood in your stool (poop). If blood is found, it could be a sign of cancer. To find out if it is cancer, your provider may order a colonoscopy.