Investigation and Analysis of the Coefficient of Variation of Internal Quality Control of Homocysteine / 现代检验医学杂志

ABSTRACT

Objective To carry out the current status of internal quality control by statistical analysis of the Internal Quality Control (IQC)data of homocysteine in 2014 March.Methods Web-based External Quality Assessment (EQA)system was used to collect IQC data of homocysteine from 292 EQA participant laboratories nationwide.The data include thecoefficient of variation (CV)of IQC data under control in March 2014 and long-term cumulative data.Acceptable rates of CVs of two-lot internal quality controls in homocysteine were calculated according to 5 criteria,that were 1/3TEa,1/4TEa and the speci-fications based on biological variation including the minimal,appropriate and optimal allowable imprecision.The instrument the participant laboratories used were sorted into 6 groups and the passing rate of each group were calculated by the 5 crite-ria.Results 292 laboratories reported the data of level 1 IQC for homocysteine,106 of which reported the data of level 2 IQC.The passing rate was different according to different criteria.The passing rate had few difference by the criteria of 1/3TEa and the minimal allowable imprecision based on biological variation,which were from 63.36% to 76.42%.It was also true for 1/4TEa and the appropriate allowable imprecision based on biological variation,which were from 34.25% to 57.55. The passing rate was only 10.62%~16.98% by the criteria of appropriate allowable imprecision based on biological varia-tion.Statistical results showed that instruments the participant mainly used were HITACHI (77/292),Olympus (61/292), Roche (19/292),Beckman (14/292),Abbott (10/292)and Simens (10/292).The passing rates of all the instrument group had few difference except Simens group.Conclusion Most of the laboratories could meet the criteria of 1/3TEa and the min-imal allowable imprecision based on biological variation.But less than half of the laboratories could meet the criteria of 1/4TEa and the appropriate and optimal allowable imprecision based on biological variation.The precision performance of ho-mocysteine among laboratories needs further improvement.