Analysis of External Quality Assessment of Maternal Serum Prenatal Screening for Down Syndrome in the First Trimester in China.

BACKGROUND: We analyzed the 2019 external quality assessment (EQA) results to evaluate the analytical performance of maternal serum prenatal screening for Down Syndrome (DS) in the first trimester in China. METHODS: In each round, five lyophilized EQA samples with detailed clinical information were distributed to participants and used to test the concentration of human chorionic gonadotropin free beta subunits (free ß-HCG) and pregnancy-associated plasma protein-A (PAPP-A) to calculate the risk value of DS. The robust coefficient of variability (CV) was calculated or test results for free ß-HCG and PAPP-A using analytes and major measurement platforms. For DS risk values, the robust CV was calculated using a professional calculation platform. Failed EQA results were analyzed using serum marker testing results and DS risk values. RESULTS: EQA results were collected from 242 laboratories in round 1 and 239 laboratories in round 2. Total acceptable rates of testing results for free ß-HCG and PAPP-A ranged from 95.04% to 97.91%. Overall acceptable rates of DS risk values ranged from 97.52% to 97.90%. The proportion of laboratories exhibiting satisfactory performance was higher in round 2 than in round 1 for serum marker testing results and DS risk values. The robust CV for risk values for each sample were significantly higher than those of serum markers. Three EQA result failure types were found, including result reporting errors, serum marker concentration testing errors, and DS risk calculation errors. CONCLUSIONS: The analytical performance of maternal serum prenatal screening for DS in the first trimester in China can be improved further.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

External Quality Assessment Program for Newborn Screening of Amino Acids in China.

BACKGROUND: To analyze the 2017 external quality assessment (EQA) results of newborn screening by MS/MS of amino acids by Chinese National Center for Clinical Laboratories, this study aimed to reflect the performance of clinical laboratories. METHODS: 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 () test was used to compare the correct recognition rates. RESULTS: EQA results were collected from 150 laboratories for Ala, Val, Arg, Leu, Met, Phe, Tyr, Cit. The overall acceptable rates of the qualitative results were 87.42%, 92.72%, 73.33%, 94.04%, 92.72%, 94.70%, 92.72%, 94.04%, respectively, and the proportion of acceptable quantitative results were 76.51 %, 91.95%, 78.38 %, 92.62%, 93.29%, 93.29%, 94.63%, 91.28%, respectively. There were significant differences in the rates of acceptable quantitative results among different items and between four methods. CONCLUSIONS: Most of the participant laboratories had satisfactory performance for the quantitative results in this EQA scheme. But for qualitative assessment, the laboratory should re-evaluate and validate their reference intervals on a regular basis to improve the consistency of clinical assessment.

Quality assessment of interpretative commenting and competency comparison of comment providers in China.

Background This study aimed to evaluate the ability of comment providers who were responsible for interpreting results in clinical laboratories in China and to improve the quality of interpretative comments. Methods Basic information and interpretative comments for five cases of 1912 routine chemistry External Quality Assessment (EQA) participant laboratories were collected by web-based EQA system in May 2018. EQA organizers assigned scores to each key phrase of comments based on predetermined marking scale and calculated total scores for each participant's answer. Final scores and ranking were calculated according to scores of cases. Finally, we comprehensively analyzed the type of hospital and the professional title of participants. Results In total, 772 clinical laboratories, 1472 participants, from different Chinese provinces submitted interpretative comments. Median scores, interquartile ranges and score ranges of the five cases were 13 (11-15, 1-20), 13 (10-16, 0-20), 15 (12-17, 0-21), 7 (5-9, -2 to 14) and 12 (10-13, -2 to 18). The final scores and ranking of participants that came from tertiary hospitals were higher than those from secondary and other hospitals; however, there were no significant differences (0.774). When grouped by professional title, we found that although no significant variability existed among senior, intermediate, junior and others (0.699), it existed between laboratory physicians and technicians, as the median final scores of the former were higher than the latter. Conclusions Practice and quality of interpretative comments are indeed different among different laboratories and participants in China. Laboratories should train and assess the interpretative ability of personnel. EQA organizers should also improve the scoring method and establish peer assessors team through this survey.

Analysis and evaluation of the external quality assessment results of quality indicators in laboratory medicine all over China from 2015 to 2018.

Background This study aimed to comprehensively evaluate laboratory quality in China and explore factors affecting laboratory errors through analyzing the external quality assessment (EQA) results of quality indicators (QIs). Methods According to model 3 (interpretive) of the proficiency testing scheme, the National Center for Clinical Laboratories of China (CNCCL) developed a questionnaire for 15 QIs. Clinical laboratories from different provinces of China participated in the EQA program of QIs annually and submitted data via an online reporting system named Clinet-EQA. The results of QIs were expressed in percentage and sigma value or minute. Three levels of quality specifications (QSs) were defined based on percentile values. Furthermore, the QIs were analyzed by disciplines, hospital scales and information construction levels of participant laboratories. Results A total of 3450 laboratories nationwide continuously attended the EQA program and submitted complete data from 2015 to 2018. The performance of most QIs has improved year by year. QIs in post-analytical gained the best performance with sigma values that varied from 5.3σ to 6.0σ. The comparison of results among different disciplines showed significant differences for five QIs. More than half of QIs had statistical differences among different hospital scales measured by hospital grades and number of hospital beds. The performance of nine QIs were influenced by information construction levels of participant laboratories. Conclusions The overall laboratory quality in China has improved since the initiation of EQA program for QIs, but the performance of some QIs was still unsatisfactory. Therefore, laboratories should make efforts for continuous quality improvement based on information provided by QSs.

External Quality Assessment of First-Trimester Prenatal Biochemical Screening in China.

BACKGROUND: Free ß subunit of human chorionic gonadotropin (free ß-hCG) and pregnancy-associated plasma protein A (PAPP-A) are two important biomarkers in first-trimester prenatal screening. This study intended to reflect their analytical performance in clinical laboratories and main platforms of the 2015 External Quality Assessment (EQA) scheme for the first-trimester biochemical screening in China. METHODS: Ten lyophilized EQA samples, divided into two sets and analyzed in two cycles 20151 and 20152, were distributed to each participant in 2015. Satisfactory performance was defined as scores more than 80 of acceptable results within the evaluation criterion of ± 30%. The robust coefficient of variability (CV) of each sample was calculated by analytes and mainstream platforms. The chi-square (2) test and the Mann-Whitney test were respectively used to compare the acceptable performance and the robust CV between two analytes, as well as two mainstream platforms. RESULTS: A total of 142 laboratories were enrolled in this EQA scheme. For free ß-hCG and PAPP-A, the number of effective results were 1330 and 1355, respectively, and the overall acceptable rates of results were 95.11% and 92.32%, respectively. For cycle 20151 and 20152, the acceptable rates were respectively 92.59% and 96.19% for free ß-hCG and 89.78% and 94.78% for PAPP-A. The 2 test showed acceptable performance differed significantly between the two analytes, as well as two platforms for PAPP-A. Significant difference of the robust CV in different analytes and platforms was demonstrated by Mann-Whitney test. CONCLUSIONS: Greater than 92% of results were acceptable. However, continuous improvement and further research of this EQA scheme is in process.

Status of External Quality Assessment on Tumor Markers in China.

BACKGROUND: The nationwide external quality assessment (EQA) of tumor markers in China has been launched for years. The quality of the performance of Chinese clinical laboratories on tumor markers is partly reflected through analysis of EQA results. This report presents an 8-year EQA result of the six most common tumor markers from 2006 to 2013. METHODS: Ten freeze-dried EQA samples were distributed to participants every year. Satisfactory performance was defined as scores of more than 80% of acceptable responses with the evaluation criterion of ± 25%. The robust coefficient of variability (CV) between laboratories and percentage difference against the target value of each sample were also calculated by year. RESULTS: A total number of 1154 laboratories submitted results in 2013, which was more than threefold of 2006. The proportion of laboratories with satisfactory performance showed an overall rising trend over the years and was up to 95% for the second survey in 2013. The overall decrease of robust CV was observed for all analytes including alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), total prostate specific antigen (t-PSA), cancer antigen 125 (CA 125), cancer antigen 15-3 (CA 15-3), and cancer antigen 19-9 (CA 19-9) except for CEA, which exhibited a rise followed by a flat trend. The percentage difference narrowed gradually and was less than 2% in 2013. CONCLUSIONS: The 8-year EQA results showed a significant enhancement of degree of harmonization of tumor markers in China. However, standardization among various testing systems and improvement of harmonization has yet to be achieved.

Neonatal screening external quality assessment in China, 2014.

OBJECTIVE: To analyze the 2014 results of neonatal screening external quality assessment (EQA) performed by the Chinese National Centre for Clinical Laboratories. METHODS: EQA test panels consisting of five dried blood spots (three panels for phenylalanine (Phe) and thyroid stimulating hormone (TSH), two for glucose-6-phosphate dehydrogenase (G6PD) and 17-alpha-hydroxy progesterone (17-OHP)) were distributed to laboratories and the results collected and evaluated. To compare the correct recognition rates, chi-square test was used. RESULTS: Test results were received from 170 laboratories for Phe, 176 for TSH, 65 for G6PD and 65 for 17-OHP. The total number of effective quantitative and qualitative results of Phe, TSH, G6PD and 17-OHP were 2520 and 2370, 2605 and 2450, 645 and 530, 645 and 645, respectively. The overall correct recognition rates for qualitative tests of Phe, TSH, G6PD and 17-OHP were 99.79 %, 99.67 %, 93.40 % and 99.84 %, and the proportion of acceptable quantitative results were 94.48 %, 98.31 %, 84.65 % and 99.84 %, respectively. There were significant differences in the rates of acceptable quantitative results of the two measurement systems for Phe, TSH and G6PD (p<0.001); χ(2) test showed significant differences in correct recognition or acceptable rates among programmes (p<0.001). CONCLUSION: Most of the quantitative results were acceptable and the overall correct recognition rates in qualitative results approached 100%. Distributing more challenging samples and increasing the range of concentrations of EQA samples will improve standards in future assessments.

[Result survey analysis of prenatal chromosome karyotyping in an external quality assessment program].

OBJECTIVE: To analyze the results of prenatal karyotype of the external quality assessment program in 2013 in order to provide references and recommendations for improving the capability and performances of karyotype analysis of prenatal screening laboratories. METHODS: Five lots of quality control cell photos were sent to 500 laboratories. The participants were asked to decide whether the photos have demonstrated any abnormal karyotype and determine the abnormal type. The results should be submitted before the deadline and compared with the standard results to evaluate the performances of the laboratory. RESULTS: One hundred forty three laboratories have returned their karyotype results for the survey. The standard answers were 7,XX,+18, 46,X,i(X)(q10), 46,XY,i(21)(q10) or 46,XY,+21,der(21;21)(q10;q10), 46,XY and 47,XY,+21 in sequential order, which were used to estimate the score of each participant. The pass rates for five lots were 97.9%, 97.2%, 95.8%, 100.0% and 97.9%, respectively. The total pass rate was 97.7%. The error rates were 2.1%, 2.8%, 4.2%, 0 and 2.1%, respectively. The total error rate was 2.3%. CONCLUSION: Some laboratories did not correctly identify the abnormal karyotypes, while some could not determine the right type of karyotype. The external quality assessment program of prenatal diagnosis of karyotype analysis should be conducted annually in order to improve the capability and performances of karyotype analysis of prenatal screening laboratories.