Calibration of ALT Measurement and External Quality Assessment

Objective To discuss the validity of using external quality assessment (EQA)for the ALT measurement calibration. Methods The effect of various K values on ALT measurement has been examined based on the continuous feedback data which has been acquired since 1999 from EQA of the National Center for Clinical Laboratory. Results Taking the target values of the EQA as the standard,the oretical K values tend to be lower than the standard one, while the K values caluculated from the continuous feedback data was closer to the standard one. Conclusion Under the circumstances of current facilities, apart from employing accredited measuring systems of ALT measurement as much as possible, data from high standard EQA may be a tentative solution as a standard to improve inter-laboratory comparability. However, this needs to be conducted after the matrix bias is removed.