3. Estimation of method reliability

3.1 Measurement conditions

Fidelity is a measure of the extent to which a method disperses repetitions, and there are many causes of dispersion. Thus, two operators applying the same method to the same sample will obtain different measurements, and we could calculate at least three fidelity values: an overall estimate, an estimate for operator 1 and another for operator 2.

Figure 8 presents a general diagram of all the sources of variation that can affect the dispersion of measurements in a laboratory. It is based on the 5Ms "Material, Manpower, Equipment (or Means), Environment, Method" and draws on the methodology described in the Eurachem guide...