Repeatability and Reproducibility Studies for Non-Replicable Tests

The paper presents several approaches to gauge repeatability and reproducibility (GRR) analysis regarding non-replicable measurements. Measurement systems have to deal with processes in which, by the nature of the measured object or by the type of measurement itself, measurements are not repeatable. In these cases, each sample unit can be measured only once. Such situations are referred as nonreplicable measurement systems. The aim of the paper is to map out the current approaches being used in GRR analysis in various cases of non-replicable tests and compare each other in order to find out the suitable use of analysis application. Approaches used are subject to critical analysis so that its review can serve a useful base for analysis of different non-replicable tests. At present, it is desirable to bring the improving actions in order to obtain the results of high quality from such kind of measurements. Since different non-replicable tests can measure a different quality characteristic, it is valuable to bring the appropriate designs for various tests. Subsequently, this review will serve an outline how to proceed in analyzing the results obtained by non-replicable tests. Specifically, GRR analysis works with two known designs named as “Crossed” and “Nested” design, which statistical software normally use. Doubtfully, crossed design is suggested to use at certain cases and nested at other specific cases. This is assessed and improving actions designed.