What is the normal range?
A normal range for a lab test is based on the test results of a very large number of people. The test results of most, but not all, patients will fall into this normal range. Some healthy patients will always have counts that are lower or higher than the normal range — that just happens to be normal for these patients. However, test results may be lower or higher than the normal range if you are ill or if you are receiving treatment. For example, a viral infection will cause your white blood cell count to go up or down. If you are receiving chemotherapy, your WBC will go down, then come back up, each time you receive treatment.
