Internal quality control status for BNP and NT-proBNP in China from 2014 to 2017.

Background This study aimed to investigate and analyze the status of internal quality control (IQC) for BNP and NT-proBNP from 2014 to 2017, so as to have an integral understanding of quality performance of measurement in clinical laboratories in China. Methods The 4-year IQC information for BNP and NT-proBNP of participant laboratories were collected through EQA reporting system. Percentages of laboratories meeting different quality requirements (pass rates) for current coefficient of variations (CVs) were calculated afterwards. Further analysis for current CVs and pass rates among different years and measurement systems were conducted. Finally, we analyzed and summarized IQC practice and its changes in 4 years. Results The current CVs for BNP and NT-proBNP have decreased significantly from 2014 to 2017, and pass rates both presented significant increasing trends. NT-proBNP had higher pass rates than BNP regardless of 1/3TEa or 1/4TEa specification was used. The main measurement systems for two analytes were different. For NT-proBNP, current CVs of Roche has decreased significantly among 4 years and were significantly lower than Radiometer and BioMerieux in 2015. Current CVs of Abbott also had decreasing tendency for BNP. Analysis of IQC practice indicated that control rules and IQC frequency had made great progress in 4 years. Conclusion The imprecision performance of measurement of BNP and NT-proBNP has improved with decreasing of current CVs and increasing of pass rates in 4 years. However, it still needs continual improvement. Clinical laboratories in China should take active actions to promote performance of BNP and NT-proBNP measurement.