title: Comparison of three distribution-free procedures in the establishment of assigned values in control sera. The establishment of assigned values in control sera, III.
abstract: Distribution-free statistical procedures should be applied to the establishment of assigned values and uncertainty intervals in a control serum. The two problems, how to find an appropriate statistical evaluation procedure and how to find an optimized experimental design, are simultaneously dealt with here: Three distribution-free procedures are presented, each based on elimination of extreme values, and 60 designs are considered differing with respect to the number of reference laboratories, of independent series, and single or double determinations. Using the data of the study described in part 1 of this series (Passing, H. et al. (1981) this j. 19, 1137-1144) we simulated these designs and the pertaining assigned values and uncertainty intervals given by each evaluation procedure. From this study one evaluation procedure is shown to be superior to others. This optimized procedure had the following characteristics: Extreme values are eliminated so that the width of the uncertainty interval is as small as possible. The median of the remaining values is the assigned value. Moreover, 6 reference laboratories are shown to be appropriate.
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D001774:Blood Chemical Analysis; D001786:Blood Glucose / Q000032:analysis; D003401:Creatine / Q000097:blood; D003402:Creatine Kinase / Q000097:blood; D006801:Humans; D011786:Quality Control; D012016:Reference Values; D013223:Statistics as Topic; D014508:Urea / Q000032:analysis; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D001786:Blood Glucose; D014508:Urea; D005723:gamma-Glutamyltransferase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D003402:Creatine Kinase; D003401:Creatine