Published: 7 Apr 2024

Reference ranges are based on the normal test results of a large group of healthy people.
Sometimes, healthy people get results outside the reference range, while people with health problems can have results in the normal range. Lab results are often shown as a set of numbers known as a reference range. A reference range may also be called 'normal values.' You may see something like this on your results: 'normal: 77-99mg/dL' (milligrams per deciliter). If your results fall outside the reference range, or if you have symptoms despite a normal result, you will likely need more testing.
Your lab results may also include one of these terms:
Negative or normal, which means the disease or substance being tested was not found
Positive or abnormal, which means the disease or substance was found
Inconclusive or uncertain, which means there wasn't enough information in the results to diagnose or rule out a disease. The range helps show what a typical normal result looks like.
But not everyone is typical. If you get an inconclusive result, you will probably get more tests.
Tests that measure various organs and systems often give results as reference ranges, while tests that diagnose or rule out diseases often use the terms listed above.

Basically, when you have blood drawn at the doctor's office, hospital or laboratory, the blood is processed in a laboratory and is then analyzed for a variety of biomarkers. A blood test can tell your healthcare provider a lot about your health, from how well you are managing diabetes and high cholesterol to whether or not you have heart disease, cancer, or another condition that has gone undetected for a long time. It can also help your doctor understand what is causing certain health conditions, and give you an early warning system so that you can take action to improve your condition or prevent it from happening in the first place.Your healthcare provider will use this information to make a diagnosis and prescribe treatment. Then, a report is prepared for your doctor to review.