Terminology Focus
Value, Measurement Signal, Result

When a laboratory measurement is reported, there are a variety of terms to describe the result. The exact terms that are preferred are listed below, with definitions from International Vocabulary of Basic and General Terms in Metrology (VIM 1993) and examples from current laboratory practice:

Value (of a quantity): magnitude of a particular quantity generally expressed as a unit of measurement multiplied by a number; EXAMPLES: amount of sodium in a sample: 4 mmol per ml; or volume of reagent powder to add to a sample: 0.5 grams.

Measurement signal: quantity that represents the measurand and which is functionally related to it; EXAMPLES: absorbance of light at a particular wavelength; electrical output of a pressure transducer; NOTE: a signal is usually converted into a result via a calibration curve.

Result (of a measurement): value attributed to a measurand, obtained by measurement.  EXAMPLES: Cholesterol level in Patient X sample: 14 mmol/l.

So, a result is a value, and these terms may both be used, although “result” is preferred since it is more closely tied to the outcome of a laboratory measurement.

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