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NCI Dictionary of Cancer Terms

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The NCI Dictionary of Cancer Terms features 8,214 terms related to cancer and medicine.

We offer a widget that you can add to your website to let users look up cancer-related terms. Get NCI’s Dictionary of Cancer Terms Widget.

reference interval
(REH-frents IN-ter-vul)
In medicine, a set of values that a doctor uses to interpret a patient’s test results. The reference interval for a given test is based on the results that are seen in 95% of the healthy population. Sometimes patients whose test results are outside of the reference interval may be healthy, and some patients whose test results are within the reference interval may have a health problem. The reference interval for a test may be different for different groups of people (for example, men and women). Also called normal range, reference range, and reference values.