Dahms, S.Kunert, J.Voss, B.Weiss, H.2004-12-062004-12-061999http://hdl.handle.net/2003/495510.17877/DE290R-6644The so-called good-laboratory-practice (GLP) test provides an experimental design and appropriate statistical analysis for the problem of analyst performance assessment in microbiological laboratories. For a given sample material multiple dilution series are generated yielding colony counts from several dilution levels. Statistical evaluation is based on the assumption of Poisson-distributed colony forming units. In this paper a new model based on conditional binomial and multinomial distributions is presented and it is shown how it is related to the standard model which assumes Poisson-distributed colony counts. The effects of common working errors on the statistical evaluation of the GLP-test are investigated.enUniversitätsbibliothek Dortmundgood-laboratory-practice-testmultinomial modelPoisson modelquality controlstandardized analytical methods310report