Using westgard's method evaluation decision chart for judging method performance of routine biochemistry items on Roche Modular PPI testing system / 中华检验医学杂志

ABSTRACT

Objective To judge method performance of routine biochemistry parameters on Roche Modular PPI testing system by using westgard's method evaluation decision chart.Methods We assessed imprecision(CV)from internal quality control and inaccuracy(bias)from external quality control evaluation.Combined estimates of imprecision and inaccuracy by plotting imprecision as the x-coordinate and inaccuracy as the y-coordinate to locate an expected operating point of every item on the chart.By comparing this operating point with allowable total errors(TEa),we can decide whether the performance is acceptable or not.Results In the 27 different parameters tested,imprecision and bias of calcium were 0.08 mmol/L and 0.06 mmol/L respectively,its performance was marginal.The imprecision of creatinine,urea,glucose, sodium,chloride and phosphorus were 3.20%,2.13%,1.52%,0.89 mmol/L,1.10% and 1.55%,the bias were 4.79%,0.96%,4.63%,0.80 mmol/L,1.74% and 4.13% respectively,their performance was good.M1 other 20 items were of excellence performance.Conclusions Routine biochemistry parameters on Roche Modular PPI testing system possessed good precision and accuracy,and their performance were acceptable.To judge method performance of biochemistry testing system by using westgard' s method evaluation decision chart was easy to do and suited for clinical laboratory.