Discussion on setting control limit of internal quality control in clinical laboratory quantitative measurement / 国际检验医学杂志

ABSTRACT

Objective To discuss the setting problem of control limit for quality control chart during the statistical quality con-trol procedure of clinical laboratory quantitative measurement.Methods The normality test of the monthly quality control data for 3 items of albumin (ALB),alanine aminotransferase (ALT)and creatinine (Cr)was performed by using the SPSS 14.0 statistical software and which was compared with the cumulated data.Results Among 30 groups of data,the normality test was inconformity in 18 groups,among 30 groups of mean t test,the differences in 20 groups showed statistical significance(P <0.05).Therefore,the calculated means and standard deviation(SD)in short term could not be directly set as the control limit of the quality control chart. Conclusion Setting the control limit of internal quality control in clinical laboratory quantitative measurement should be according to the guidance of C24-A3 document in CLSI.The SD estimated value obtained from large amount stable quality control data or the 6-month cumulative values is recommended to be used as SD of the new batch number,which should be regularly assessed.