The degree to which a measurement, or an estimate based on measurements, represents the true value of the attribute that is being measured. In the laboratory, a. of a test is determined when possible by comparing results from the test in question with results generated using reference standards or an established reference method.
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ac·cu·ra·cy (akґu-rə-se) the closeness of the expected value to the true value of the measured or estimated quantity; a measure that depends on both precision and bias. Cf. precision (def. 1).Medical dictionary. 2011.