Distributions of results of cetirizine dihydrochloride assay in bulk material

The distribution of the cetirizine dihydrochloride assay results in correlation with the pharmacopoeia limits is analyzed. The data for analysis were obtained at Chemagis Ltd., Israel, for 13 batches during a year in two laboratories by five analysts using three different titroprocessors (total 114 results of the determination). The hypothesis on the normal distribution of the data was tested using omega(2)-criterion and accepted at the level of confidence 0.90. A control chart is designed for indication of warning and action limits of the determination results and for diagnoses of outliers in the further titrations. The distribution of the analyte content in different batches and the distributions of the titration results at the pharmacopoeia limits were plotted. The probabilities of the erroneous decisions of Type 1 and Type 2 on the batch quality were calculated from these distributions.