Uncertainty in semi-qualitative testing

The problem of assigning uncertainty-like statements to qualitative test results still remains widely unsolved, although the volume of not purely quantitative testing and analysis, and their economic impact are immense. A pragmatic approach is developed for the assessment of measurement uncertainty for procedures where a complex characteristic (e.g. of a material) discontinuously changes in dependence on one or more recordable, continuous quantitative parameters, and the change of the characteristic is assessed by judgement (which may be instrument-assisted). The principles of the approach are discussed, and an application example is given.