Notes

NOTE 1 The concept 'measurement accuracy' is not a quantity and is not given a numerical quantity value. A measurement is said to be more accurate when it offers a smaller measurement error.

NOTE 2 The term “measurement accuracy” should not be used for measurement trueness and the term “measurement precision” should not be used for 'measurement accuracy', which, however, is related to both these concepts.

NOTE 3 'Measurement accuracy' is sometimes understood as closeness of agreement between measured quantity values that are being attributed to the measurand.

Annotations

ANNOTATION (informative) [5 June 2014] Here "quantity value" can be replaced with "value" without ambiguity: "closeness of agreement between a measured value and a true value of a measurand".

ANNOTATION (informative) [9 June 2016] Historically, the term "measurement accuracy" has been used in related but slightly different ways. Sometimes a single measured value is considered to be accurate (as in the VIM3 definition), when the measurement error is assumed to be small. In other cases, a set of measured values is considered to be accurate when both the measurement trueness and the measurement precision are assumed to be good. Sometimes a measuring instrument or measuring system is considered to be accurate, in the sense that it provides accurate indications. Care must therefore be taken in explaining in which sense the term "measurement accuracy" is being used. In no case is there an established methodology for assigning a numerical value to measurement accuracy.

1 Quantities and units

• 1.1 quantity
• 1.2 kind of quantity
• 1.3 system of quantities
• 1.4 base quantity
• 1.5 derived quantity
• 1.6 International System of Quantities
• 1.7 quantity dimension
• 1.8 quantity of dimension one
• 1.9 measurement unit
• 1.10 base unit
• 1.11 derived unit
• 1.12 coherent derived unit
• 1.13 system of units
• 1.14 coherent system of units
• 1.15 off-system measurement unit
• 1.16 International System of Units
• 1.17 multiple of a unit
• 1.18 submultiple of a unit
• 1.19 quantity value
• 1.20 numerical quantity value
• 1.21 quantity calculus
• 1.22 quantity equation
• 1.23 unit equation
• 1.24 conversion factor between units
• 1.25 numerical value equation
• 1.26 ordinal quantity
• 1.27 quantity-value scale
• 1.28 ordinal quantity-value scale
• 1.29 conventional reference scale
• 1.30 nominal property

2 Measurement

• 2.1 measurement
• 2.2 metrology
• 2.3 measurand
• 2.4 measurement principle
• 2.5 measurement method
• 2.6 measurement procedure
• 2.7 reference measurement procedure
• 2.8 primary reference measurement procedure
• 2.9 measurement result
• 2.10 measured quantity value
• 2.11 true quantity value
• 2.12 conventional quantity value
• 2.13 measurement accuracy
• 2.14 measurement trueness
• 2.15 measurement precision
• 2.16 measurement error
• 2.17 systematic measurement error
• 2.18 measurement bias
• 2.19 random measurement error
• 2.20 repeatability condition of measurement
• 2.21 measurement repeatability
• 2.22 intermediate precision condition of measurement
• 2.23 intermediate measurement precision
• 2.24 reproducibility condition of measurement
• 2.25 measurement reproducibility
• 2.26 measurement uncertainty
• 2.27 definitional uncertainty
• 2.28 Type A evaluation of measurement uncertainty
• 2.29 Type B evaluation of measurement uncertainty
• 2.30 standard measurement uncertainty
• 2.31 combined standard measurement uncertainty
• 2.32 relative standard measurement uncertainty
• 2.33 uncertainty budget
• 2.34 target measurement uncertainty
• 2.35 expanded measurement uncertainty
• 2.36 coverage interval
• 2.37 coverage probability
• 2.38 coverage factor
• 2.39 calibration
• 2.40 calibration hierarchy
• 2.41 metrological traceability
• 2.42 metrological traceability chain
• 2.43 metrological traceability to a measurement unit
• 2.44 verification
• 2.45 validation
• 2.46 metrological comparability of measurement results
• 2.47 metrological compatibility of measurement results
• 2.48 measurement model
• 2.49 measurement function
• 2.50 input quantity in a measurement model
• 2.51 output quantity in a measurement model
• 2.52 influence quantity
• 2.53 correction

3 Devices for measurement

• 3.1 measuring instrument
• 3.2 measuring system
• 3.3 indicating measuring instrument
• 3.4 displaying measuring instrument
• 3.5 scale of a displaying measuring instrument
• 3.6 material measure
• 3.7 measuring transducer
• 3.8 sensor
• 3.9 detector
• 3.10 measuring chain
• 3.11 adjustment of a measuring system
• 3.12 zero adjustment of a measuring system

4 Properties of measuring devices

• 4.1 indication
• 4.2 blank indication
• 4.3 indication interval
• 4.4 nominal indication interval
• 4.5 range of a nominal indication interval
• 4.6 nominal quantity value
• 4.7 measuring interval
• 4.8 steady-state operating condition
• 4.9 rated operating condition
• 4.10 limiting operating condition
• 4.11 reference operating condition
• 4.12 sensitivity of a measuring system
• 4.13 selectivity of a measuring system
• 4.14 resolution
• 4.15 resolution of a displaying device
• 4.16 discrimination threshold
• 4.17 dead band
• 4.18 detection limit
• 4.19 stability of a measuring instrument
• 4.20 instrumental bias
• 4.21 instrumental drift
• 4.22 variation due to an influence quantity
• 4.23 step response time
• 4.24 instrumental measurement uncertainty
• 4.25 accuracy class
• 4.26 maximum permissible measurement error
• 4.27 datum measurement error
• 4.28 zero error
• 4.29 null measurement uncertainty
• 4.30 calibration diagram
• 4.31 calibration curve

5 Measurement standards (Etalons)

• 5.1 measurement standard
• 5.2 international measurement standard
• 5.3 national measurement standard
• 5.4 primary measurement standard
• 5.5 secondary measurement standard
• 5.6 reference measurement standard
• 5.7 working measurement standard
• 5.8 travelling measurement standard
• 5.9 transfer measurement device
• 5.10 intrinsic measurement standard
• 5.11 conservation of a measurement standard
• 5.12 calibrator
• 5.13 reference material
• 5.14 certified reference material
• 5.15 commutability of a reference material
• 5.16 reference data
• 5.17 standard reference data
• 5.18 reference quantity value