Clinical and laboratory tests in clinical medicine include a range of measurements that may be categorized as “normal range” tests, positive or negative tests, or contextual tests. Normal range test results are quantitative and are compared to a reference interval or range provided by the laboratory. Positive or negative tests are also quantitative tests and characteristically have a cutoff value that specifies the result. Contextual tests require a context, a physiological condition, to correctly interpret the result. A closer examination of reference intervals suggests that these also are contextual. The fact that there is a range of apparently normal values indicates the presence of cultural, biological, physiological and behavioral diversity in the population sampled to determine normality. As such, the reference interval describes the population from which it was determined and may have utility in this regard.
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Corresponding author: Alan N. Charney, MD, Clinical Professor, Department of Internal Medicine, NYU Langone Health, Division of Nephrology, 550 1st Avenue, New York, NY 10016, USA; and 47 Laura Lane, Morristown, NJ 07960, USA, E-mail:
Diagnosis aims at answering the question how diagnosis determines the quality of medical care. It focuses on how diagnosis can be advanced, how it is taught, and how and why it can fail, leading to diagnostic errors. The journal welcomes both fundamental and applied works, improvement initiatives, opinions, and debates to encourage new thinking on improving this critical aspect of healthcare quality.
22 Jan 2014
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