accuracy

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ac·cur·a·cy

(ak'kū-ră-sē), Do not confuse this word with precision.
The degree to which a measurement, or an estimate based on measurements, represents the true value of the attribute being measured. In the laboratory, accuracy 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.

accuracy

The degree to which, on average, a test represents the true value—i.e., is unbiased.

Lab medicine
The extent to which a value from a test reflects or agrees with the reference value of the analyte being tested, measured statistically by standard deviations; the proportion of correct outcomes of a method (often used interchangeably with concordance in two-by-two tables).

Accuracy is insufficient for describing the performance of medical tests and deciding when to use what, because accuracy has two separate components and depends on the prevalence of the condition for which the test is appropriate. The degree of reproducibility of test results, regardless of whether or not they are accurate, are measured statistically by the coefficient of variation; the degree to which a measurement (e.g., the mean estimate of a treatment effect) is true or correct. An estimate can be accurate, yet not be precise, if it is based upon an unbiased method that provides observations having great variation—i.e., not close in magnitude to each other.

accuracy

Lab medicine The extent to which a value from a test reflects or agrees with the reference value of the analyte being tested, measured statistically by standard deviations; the proportion of correct outcomes of a method–often used interchangeably with concordance. See Coefficient of variation, Diagnostic accuracy, Inaccuracy, Two-by-two table. Cf Precision.

ac·cur·a·cy

(ak'kyūr-ă-sē)
The degree to which a measurement represents the true value of the attribute that is being measured; refers to the closeness of an analytic result to an actual result.
References in periodicals archive ?
Why is it necessary to test for both accuracy and precision?
Both accuracy and precision are necessary in order to ensure that results are valid.
The US FDA sets high standards for ensuring that calibrated equipment meets pre-established accuracy and precision limits:
Attention to the accuracy and precision of pipettes and other liquid-handling devices improves confidence and quality in laboratory-analytical testing.
A horizontal furnace design elemental analyzer has been number one in terms of accuracy and precision in the last three independent Royal Society of Chemistry, Micro Analytical Group tests.
Nearly all commercially available microanalysis instruments can be demonstrated to give acceptable data accuracy and precision on selected samples.
Accuracy and Precision (Horizontal Furnace Design) Sample Run %C %H %N 1 65.43 6.72 8.45 2 65.47 6.73 8.45 3 65.47 6.72 8.48 4 65.45 6.70 8.44 5 65.44 6.72 8.47 6 65.50 6.72 8.52 7 65.52 6.70 8.52 8 65.48 6.70 8.49 9 65.45 6.70 8.48 10 65.49 6.71 8.48 Mean values 65.47 6.71 8.48 Theoretical values 65.44 6.71 8.45 Deviation from theory 0.03 0.00 0.03 Operating details: Combustion temperature 975 C; Reduction temperature 600 C; Oven temperature 81 C; Combustion time 60 seconds; Weighing capsules high purity tin; Calibration standard OAS Acetanilide Table 2.