This part of ISO 11843 is concerned with calibration functions that are either linear or non-linear.
It specifies basic methods to
-- construct a precision profile for the response variable, namely a description of the standard deviation (SD)
or coefficient of variation (CV) of the response variable as a function of the net state variable,
-- transform this precision profile into a precision profile for the net state variable in conjunction with the
calibration function, and
-- use the latter precision profile to estimate the critical value and minimum detectable value of the net state
variable.
The methods described in this part of ISO 11843 are useful for checking the detection of a certain substance
by various types of measurement equipment to which ISO 11843-2 cannot be applied. Included are assays of
persistent organic pollutants (POPs) in the environment, such as dioxins, pesticides and hormone-like
chemicals, by competitive ELISA (enzyme-linked immunosorbent assay), and tests of bacterial endotoxins
that induce hyperthermia in humans.
The definition and applicability of the critical value and minimum detectable value of the net state variable are
described in ISO 11843-1 and ISO 11843-2. This part of ISO 11843 extends the concepts in ISO 11843-2 to
the cases of non-linear calibration.
The critical value, Xc, and minimum detectable value, xd, are both given in the units of the net state variable. If
xc and xd are defined based on the distribution for the response variable, the definition should include the
calibration function to transform the response variable to the net state variable. This part of ISO 11843 defines
xc and xd based on the distribution for the net state variable independently of the form of the calibration
function. Consequently, the definition is available irrespective of the form of this function, whether it is linear or
non-linear.
The calibration function should be continuous, differentiable, and monotonically increasing or decreasing.
A further method is described for the cases where the SD or CV is known only in the neighbourhood of the
minimum detectable value.
Examples are provided.
ISO 11843-5:2008 Referenced Document
ISO 11843-1:1997 Capability of detection - Part 1: Terms and definitions
ISO 11843-2:2000 Capability of detection - Part 2: Methodology in the linear calibration case
ISO 3534-1 Statistics — Vocabulary and symbols — Part 1: General statistical terms and terms used in probability
ISO 3534-2 Statistics - Vocabulary and symbols - Part 2: Applied statistics
ISO 3534-3 Statistics-Vocabulary and symbols-Part 3:Design of experiments*, 2024-04-19 Update
ISO 5725-1 Accuracy (trueness and precision) of measurement methods and results — Part 1: General principles and definitions*, 2023-07-01 Update
ISO 11843-5:2008 history
2017ISO 11843-5:2008/Amd 1:2017 Capability of detection - Part 5: Methodology in the linear and non-linear calibration cases; Amendment 1
2008ISO 11843-5:2008 Capability of detection - Part 5: Methodology in the linear and non-linear calibration cases