External Quality Assessment Program for Newborn Screening of Acylcarnitine in China, 2018

The aim of this study was to analyze the 2018 external quality assessment (EQA) results of newborn screening by MS/MS of acylcarnitine by Chinese National Center for Clinical Laboratories and to determine the performance of clinical laboratories.

Five dried blood spots were distributed to participants every round. Satisfactory performance was defined as scores more than 80 of acceptable results within the evaluation criterion. The robust coefficient of variability (RCV) of each sample was calculated by measurement systems. The chi-square (2) test was used to compare the correct recognition rates.

EQA results were collected from 150 laboratories for 15 different acylcarnitines between C0 - C18. The overall acceptable rates of the qualitative results were between 81.21% and 96.67%, and the proportion of acceptable quantitative results were between 78.38% and 93.24%. There were significant differences in the rates of acceptable quantitative results among different items and between the four methods.

Most of the participant laboratories had satisfactory performance for the quantitative results in this EQA scheme. But for qualitative assessment, a laboratory should re-evaluate and validate their reference intervals on a regular basis to improve the consistency of clinical assessment.