ABSTRACT
Objective The main purpose is to establish a simple method of analytical run length definition through combination of control-based quality control(QC) and average of normals method(AON).Methods Eight test items with different analytical performance were chosen.First,the individualized control-based quality control strategy was designed in the direction of sigma metrics,and the suitable AON rules were selected for each analyte.Then,the selected AON rules were applied to the patient data of successive five workdays.Meanwhile,new individualized control-based QC procedures were also used at 8:00,10:00,12:00 and 14:00 in those days.At last,AON QC result were compared with control-based QC result to define the analytical run for 8 items and the strategy through which laboratory can optimize analytical run length.Results The error detection power of AON algorithms was as good as control-based QC whose performance was excellent.Analytical run length for 8 items involved in this study were defined as follows:triglyceride,potassium,total protein: 8 hours,Chlorine: 6 hours,magnesium:4 hours,calcium,carbon dioxide combining power,sodium: 2 hours.Conclusions For the items with performance above 3.5 sigma,the analytical run was defined mainly depending upon control-based QC,and AON QC was just used to validate control-based result.For the items with performance below 3.5 sigma,the analytical run was defined mainly depending upon AON QC.