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Objective:To establish and evaluate a new real-time quality control method that can identify the random errors by using the backpropagation neural network (BPNN) algorithm and taking blood glucose test as an example.Methods:A total of 219 000 blood glucose results measured by Siemens advia 2 400 analytical system from January 2019 to July 2020 and derived from Laboratory Information System of Beijing Chaoyang Hospital Laboratory Department was regarded as the unbiased data of our study. Six deviations with different sizes were introduced to generate the corresponding biased data. With each biased data, BPNN and MovSD algorithms were used and tested, and then evaluated by traceability method and clinical method.Results:For BPNN algorithm, the block size was pre-set to 10 and the false-positive rate in all biases was within 0.1%. For MovSD, however, the optimal block size and exclusive limit were 150 and 10% separately and its false-positive rate in all biases was 0.38%, which was 0.28% higher than BPNN. Especially, for the least two error factors of 0.5 and 1, all the random errors were not detected by MovSD; for the error factor larger than 1, random errors could be detected by MovSD but the MNPed was higher than that of BPNN under all deviations. The difference was up to 91.67 times. 460 000 reference data were produced by traceability procedure. The uncertainty of BPNN algorithm evaluated by these reference data was only 0.078%.Conclusion:A real-time quality control method based on BPNN algorithm was successfully established to identify random errors in analytical phase, which was more efficient than MovSD method and provided a new idea and method for the identification of random errors in clinical practice.
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Objective:To establish a candidate reference procedure for the enumeration of cell particles in urine and applied to the multi-center performance evaluation of an automated urine formed elements analyzer.Methods:According to the standardized mannual microscopic examination of fresh non-centrifuged urine samples and the recommended reference method for enumeration of cell particles in urine published by ISLH, we established a candidate reference procedure for the enumeration of cell particles in urine. From four class A tertiary hospitals′ clinical laboratories, three rigorous trained technicians per hospital tested the same specimen respectively using the reference procedure. Each specimen was repeatedly counted 5 times, obtaining the quantitative results of cell particles were obtained in urine. Four hospitals used the established candidate reference measurement procedure and the automated urine formed elements analyzer to detect 40 to 60 urine specimens from September 2020 to January 2021, and evaluate the established reference method, meanwhile evaluate the accuracy and consistency of the each count from automated urinalysis analyzer.Results:Using the candidate reference measurement procedures, the coefficient of variation of results derived from three trained technicians per hospital was less than 6.98% (red blood cells), 6.99% (white blood cells), 13.94% (epithelial cells) and met the quality requirements. The performance evaluation results of automated urine formed elements analyzer showed that the accuracy of red blood cells, white blood cells and epithelial cells met the requirements (bias≤4.98%) and was well consistent with the reference measurement procedure ( R2≥0.989). Conclusions:A candidate reference measurement procedure for the enumeration of urine cell particles was successfully established with satisfactory precision and accuracy. This procedure was applied to multicenter performance evaluation of an automated urine formed elements analyzer with good accuracy and consistency.
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Objective:To prepare the control materials of point-of-care(POC) glucose testing and evaluate their homogeneity, stability and matrix effects.Methods:The high, medium and low concentration control materials were prepared from patient leftover whole blood, which was centrifuged, fixed, washed, filtered, and aliquoted. The homogeneity and stability of the control materials were evaluated according to CNAS (China National Accreditation Service for Conformity Assessment, CNAS) GL29:2010"Reference materials-General and statistical principles for certification". The control materials were used to evaluate the matrix effects in POC glucose detection systems by Deming regression, according to the Clinical and Laboratory Standards Institute (CLSI) EP14-A3. Meanwhile, these control materials were used as the internal quality control, and their coefficients of variation ( CV) were calculated. One-way ANOVA and t-Test were used to analyze the results. Results:The homemade materials at three concentrations showed good homogeneity[ F< F0.05(9, 20)]. When the control materials were stored at 2-8 ℃, the stable phases for the opened and closed bottles were 10 days and 15 days, respectively, and there was no statistically significant difference between the results of the first day( P>0.05). The control materials at three concentrations also showed good applicability and there were no matrix effects in 10 POC glucose systems. When the control materials were detected in the internal quality control, the CVs of the high, medium and low concentrations were 0.63%, 0.66% and 1.65%, respectively, which were all below 7.5%. Conclusions:The homemade human control materials of POC glucose testing showed good homogeneity, stability and applicability. They met the requirements of quality control in hospital settings, which provided a good application prospect of the quality management of POC glucose testing.
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Objective:To investigate the application value of establishing the differential diagnosis model of pulmonary tuberculosis using routine laboratory data.Methods:The retrospective study was conducted. The routine laboratory data of newly diagnosed patients with pulmonary tuberculosis and other pulmonary diseases in Beijng Jishuitan Hospital and Beijing Hepingli Hospital from May 2015 to November 2021were collected. According to the random numbers showed in the computer, all the 11516 patients were divided into training dataset and test dataset with a ratio of 9∶1. Four machine learning algorithms, Support Vector Machine, Random Forest, K-Nearest Neighbor and Logistic Regression, were used to build models and select features. The diagnostic accuracy of each model was verified by using the 10-fold cross-validation method and the performance of each model was evaluated by using the receptor operator of characteristic (ROC) curve.Results:Random Forest was selected as the optimal machine learning algorithm to build the best feature model in the study. According to importance scale of factors, the differential diagnosis model of pulmonary tuberculosis consisting of 37 non-specific test indexes. In the validation set and test set the accuracy and area under curve (AUC) of the models were 0.747 and 0.736, the sensitivity, specificity and accuracy were 68.03% and 68.75%, 70.91% and 67.90%, 70.30% and 68.12%, respectively.Conclusion:A key tool in the differential diagnosis model of pulmonary tuberculosis was established by routine laboratory data in combination with machine learning. The results of this study need to be further verified by more data from medical institutions.
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Objective:To establish a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) method for the direct detection of serum M protein without antibody enrichment, and to assess its detection performance.Methods:Method establishment. A total of 712 waste serum samples were collected from patients who applied for the M protein identification test in Beijing Chaoyang Hospital affiliated to Capital Medical University. The immunoglobulin light chain was obtained by reduction of IgG and IgA by TCEP, and the detection method was preliminarily determined. The waste serum samples from 20 healthy people were collected to determine the range of mass-to-charge ratios of κ and λ light chain ions. 8 parallel tubes and 8 batches were set up for intra-and inter-batch reproducibility evaluation. 10-fold, 100-fold and 200-fold diluted M protein from 23 positive samples were detected by established MALDI-TOF MS method, and its sensitivity was evaluated. 3 methods of IFE, SPE and MALDI-TOF MS were used to detect M protein simultaneously, and the coincidence rate between MALDI-TOF MS and IFE and SPE was calculated.Results:The repeatability within and between batches was 100%, respectively. The original, 10-, 100-and 200-fold dilutions of 23 M protein-positive samples were determined, and the detection limit of MALDI-TOF MS for M protein was 0.06-0.18 g/L. IFE as the gold standard, the overall coincidence rates of SPE and MALDI-TOF MS were 85.9% and 92.3%, respectively, and the positive coincidence rates of SPE and MALDI-TOF MS were 72.8% and 99.7%, respectively, of the 712 samples. Among the different types of M-proteins, MALDI-TOF-MS agreed 100% with IFE M-protein results for IgA, IgD, IgM, free light chain type and biclonal group, while the agreements of SPE for IgM, IgA and free light chain samples were only 66.7%, 58% and 19.5%, respectively. One positive sample in the IgG group was not detected by MALDI-TOF MS. 23 M-proteins positive samples were diluted by original, 10, 100 and 200 times to access the sensitivity of MALDI-TOF MS method. The coincidence rate of MALDI-TOF MS was 100% and IFE was 96% at 10-fold dilution. The coincidence rate of IFE was 28% and 23% of MALDI-TOF MS at 100-fold and 200-fold dilution, respectively.Conclusions:A MALDI-TOF MS method for the detection of serum M-proteins was successfully established. This method has the advantages of high detection throughput, fast speed, good sensitivity, specificity and coincidence rate.
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Objective:To establish the sex-, age-and season-specific (month) reference intervals (RI) for thyroid stimulating hormone (TSH) measurement by big data and indirect method in adults.Methods:TSH data of anonymous patients were collected from Beijing Chaoyang Hospital Affiliated to Capital Medical University in 2016, the data were selected and outliers were removed. Indirect methods (Hoffmann method and Bhattacharya method) were used to calculate TSH reference intervals of whole population, different genders, ages and seasons (months). TSH RI from two indirect methods of total population, selected population, physical examination population was compared with RI from reagent instruction according to reference change value ( RCV) based on biological variability. Results:A total of 61 599 records were obtained from 90 699 records including 18 776 males and 42 823 females. The TSH RI were obtained by Hoffmann method: the whole population, 0.59-5.59 μIU/ml (1 μIU/ml=1 mIU/L), male, 0.53-5.16 μIU/ml, female, 0.59-6.11 μIU/ml. The upper limits of TSH RI were higher with age and in winter (January): 18-30 years old, 0.62-5.57 μIU/ml, 71-80 years old, 0.49-6.45 μIU/ml; January, 0.59-6.40 μIU/ml, August, 0.60-5.56 μIU/ml; The RI of TSH by Bhattacharya method: the whole population, 0.58-5.80 μIU/ml, male, 0.55-5.02 μIU/ml, female, 0.62-6.21 μIU/ml. The upper limits of TSH RI were also higher with age and in winter (January): 18-30 years old, 0.65-5.67 μIU/ml, 71-80 years old, 0.46-5.99 μIU/ml, January: 0.61-6.52 μIU/ml, August: 0.61-5.69 μIU/ml. Compared to RI from reagent instruction, the differences of TSH RI from two indirect methods of total population, selected population, physical examination population were acceptable.Conclusions:TSH RI was established by indirect method. With the increase of age and winter, the upper limit of TSH reference interval tends to increase.
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The outbreak of 2019 Novel Coronavirus (2019-nCoV) has spread from Wuhan to the whole country. After the Spring Festival, workers will return to workplace and students will return to school. There is an increasing risk of 2019-nCoV cases being imported into provinces and cities. In order to promote the prevention and control of 2019-nCoV infection, reduce the risk of transmission in medical institutions, and ensure medical quality and medical safety, it is necessary to carry out the detection test of 2019-nCoV in biosafety class II laboratory. In order to achieve the goal of zero infection of the laboratory personnel, different preventive measures should be taken to assess the risk of the experimental activities.
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In order to promote the prevention and control of 2019-nCoV infection, reduce the risk of transmission in medical institutions, and ensure medical quality and medical safety, it is necessary to carry out the detection test of 2019-nCoV in biosafety class Ⅱ laboratory. In order to achieve the goal of zero infection of the laboratory personnel, different preventive measures should be taken to assess the risk of the experimental activities.
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Objective@#To investigate the potential improvement of sample quality by automatic pre-analysis sample checking system, comparing to visual inspection for coagulation tests routinely.@*Methods@#Thirty samples with hemolysis, Icteric and lipemia in different levels were prepared and issued to 13 technicians for visual check, to evaluate the consistency individually. 2 949 blood samples with order for coagulation test were collected in Beijing Chaoyang Hospital in April and May 2018, the quality of all samples was evaluated by both visual check and automatic sample quality checking system before analysis, performance of two measurements detecting hemolysis, lipid, icteric or clot was compared.@*Results@#Significant differences were found in visual check among operators. The Kappa coefficients in three randomly selected groups were 0.32, 0.26 and 0.38 respectively, indicating that the consistency of visual check was poor. Among all investigated samples, 3 samples with unacceptable interference were detected visually, including 2 samples with hemolysis and another one with lipemia. On the other hand, 19 unqualified samples were identified by automatic checking system. Five types of interference of unqualified samples were detected as icteric (26.32%,5/19), clot (21.05%,4/19) hemolysis (5.26%,1/19),lipemia (36.84%, 7/19), and hemolysis with lipemia (10.53%,2/19) respectively by automatic checking system. But one case of hemolysis sample rejected by visual check was not rejected by automatic sample quality checking system.7 samples were merely affected on D-dimer by lipemia, which level did not influence the results of prothrombin time(PT) and activated partial thromboplastin time (APTT). Notably, other two samples were interfered with not only tests of PT, APTT and fibrinogen by hemolysis, but also D-dimer by the considerable level of lipemia, which showed the superiority of test-specific quality checking features.@*Conclusions@#The automatic pre-analysis sample quality checking system can improve the detection rate of unqualified samples and improve the efficiency of routine, helping realization of total quality management.
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Objective To prepare the trueness verification materials of C-reactive protein (CRP) and evaluate its homogeneity, stability and commutability. Methods The high and low CRP concentrations trueness verification materials were from patient leftover sera which were pooled, mixed thoroughly, filtered and aliquoted. The homogeneity, stability and commutability of these materials were evaluated according to CNAS(China National Accreditation Service for Conformity Assessment, CNAS)-GL29:2010 "Reference materials-General and statistical principles for certification (ISO Guide35:2006)"and the Clinical and Laboratory Standards Institute (CLSI) EP30A. The trueness verification materials were used to evaluate the commutability in 10 clinical CRP detection systems, using forty-five patients' leftover sera with different CRP concentration evaluated by Deming regression in EP30A of CLSI. Meanwhile, the commutability of dilution series of ERM DA-474/IFCC were evaluated using the same method. Results A total of two CRP concentration level trueness verification materials were prepared, with high and low concentration levels of 754 and 743 vials, 1 ml each, respectively. The preparation showed good homogeneity (F<F0.05(14,30);On the condition of room temperature, 2-8 ℃ and -80 ℃, these materials were stable for 7 days and 44 months respectively, the slope of the linear equation of | b1 | less than t0.95,n-2 · s(b1), there was no statistically significant difference between the slope and zero, the stability is satisfied. The materials and the dilution series of ERM-DA 474/IFCC also showed good commutability among patient sera in 10 systems. Conclusions The trueness verification materials of C-reactive protein (CRP) showed good homogeneity, stability and commutability. The dilution series ERM DA-474/IFCC also have good commutability. These provided experimental support for the value transfer and application of the trueness verification materials .
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Objective To explore the CRP harmonization by calibration using commutable trueness verification materials. Methods High and low level of CRP concentrations trueness verification materials(H and L) were prepared by Beijing center for clinical laboratories. Thesetrueness verification materials were diluted to 5 calibration points(5L, 4L+1H, 3L+2H, 1L+4H, 5H) by weighing method, respectively. These 5 points were used to calibrate four different brands of CRP detection system (Diasys, Leadman, Siemens and Roche) instead of the original procedure. Sera from 21 patients and the international standard ERM DA-474/IFCC were used to compare harmonization and trueness after calibration. Each sample above was measured twice. Results After calibration, the median of CV was reduced from 19.33％ to 2.92％ among 21 patient samples, less than the optimal CV based on biological variability (CV=10.6％). Compared with Desai, the slopes were closer to 1 from 0.90-1.09 to 0.93-0.96 after calibration. Meanwhile, if ERM-DA474/IFCC was used as the trueness verification materials, the absolute bias wasreduced from 3.08-11.07 mg/L to 0.52-2.97 mg/L which was close to theuncertainty of itself (2.5 mg/L). Conclusions Afterthe calibration which contained five linear concentration points of CRP trueness verification materials by weighing method, both harmonization and trueness of CRP were improved.
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English for medical laboratory is an instrumental course,which aims to develop students'competency in reading English literature,writing English scientific papers and conducting international academic exchanges in English.With the continuous expansion and deepening of international exchange and cooperation in laboratory medicine and the demands for training international talents in higher education in China,higher requirements have been put forward for the teaching quality of this course.According to the post competency requirements for professionals of medical laboratory,this paper mainly discusses the teaching mode of English for medical laboratory from the aspectsof educational concept,teaching material construction,teaching mode,assessment mechanism and teachers,hoping to play an active role in the teaching reform of English for medical laboratory at the undergraduate level.
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Rapid diagnosis is important for the prevention and control of infectious disease.Point-of-care testing (POCT) technology is simple,mobile,rapid,sensitive and accurate.In recent years,POCT has been widely used in the detection of infectious agents.This article reviews the development of POCT in the diagnosis of infectious diseases,focusing on immuno-chromatographic technology,microfluidic chip technology and loop-mediated isothermal amplification (LAMP) technology.
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Point-of-care testing is also called near-patient testing that is performed near or at the site of a patient with the result leading to possible change in the care of the patient.With the rapid development of sensor technology and new biomarkers,a great of diagnostic tests are transformed into POCT products and serve for doctors.This article will introduce the advantages and disadvantages of POCT in clinical application,compare core issues of POCT with different countries abroad in quality management,analyze the role of informatization of POCT and explore new clues of standardized POCT management.
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Objective To value C-reactive protein ( CRP ) trueness verification materials and to perform the CRP trueness verification program in Beijing .Methods The CRP value of trueness verification materials were assigned by the international reference material ERM DA-474/IFCC, using 10 clinical routine detection systems at departments of clinical laboratory of Beijing Chaoyang and Luhe Hospital Affiliated to Capital Medical University .The calibration curves with 4 ERM DA-474/IFCC dilutions were established and used for value transfer for trueness verification materials of two levels .The uncertainty was also assessed during the process.Then, the trueness verification was performed in the EQA at Beijing Center for Clinical Laboratories ( BCCL ) among 42 clinical laboratories.The samples were distributed according to BCCL standard operating procedure .The Microsoft Excel 2007 and SPSS 17.0 were used to process the results and the function of efficiency ( En) was calculated to verify the difference between the value and the overall mean of all participating laboratories .Results The values and uncertainties of two trueness verification materials of CRP were (109.9 ±9.4) mg/L and (27.1 ±2.4) mg/L respectively.The results of trial application of two level trueness verification materials in the EQA at Beijing Center for Clinical Laboratories (BCCL) were satisfied.There were no significant difference between the transfer values from our study and the values from means of all laboratories in Beijing .The function of efficiency ( En ) was less than 1.Conclusions The valueswhich were established by using multiple detection platforms for CRP trueness verification materialswere accurate and the uncertainties were small .This method is a preferably method for CRP value assignment because there was no suitable reference method for CRP measurement till now .Thematerialswere suitable for the trueness verification program for clinical laboratories in Beijing .
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Objective To compare and study the two kinds of quality control methodologies related to intelligent quality management system ( iQM) and traditional quality control , and the quality control performance of iQM equivalent to traditional quality control were evaluated , ensuring the accuracy of the results of blood gas testing.Methods Beijing Chaoyang Hospital of Capital Medical University , Beijing Tiantan Hospital of Capital Medical University , Shanghai Longhua Hospital of Shanghai University of Chinese Medicine, and Sichuan Provincial People′s Hospital, these 4 medical institutions were selected to implement this study.During the period from June 2016 to December 2016, in the routine detection of total 3 712 specimen, the iQM and traditional quality control modes were used simultaneously to calculate the mean values of all blood gas parameters quality controls , SD, CV (%) and Sigma values, to evaluate the quality control performance and difference of the two quality control modes .Results During the process of testing blood gas samples from 3 712 specimen in 4 hospitals, iQM process control solution ( PCS) A, B, C ran 1 089, 7 678 and 154 quality control samples respectively , and 732 external quality control samples were run by traditional quality control mode .Considering the most sensitive parameters of blood gas testing pO 2, iQM PCS A, B, C′s Sigma value are higher than 8, however, the traditional quality control′s Sigma value are less than 6; For parameters pCO2, pO2and Na+, there exists significant difference between two quality control methods (P＝0.004 8,P＝0.000 1,P＝0.004 4,P＜0.01), other parameters pH, K+, Ca ++, Glu, Lac and Hct, there exists no significant difference between two quality control methods (P＝0.250 6, P＝0.062 3,P＝0.034 0,P＝0.346 9,P＝0.186 3,P＝0.823 1,P＞0.01).Totally 22 errors detected by iQM, includes 14 micro-clots and 8 interferences samples, which were not detected by traditional quality control .Conclusions The error in blood gas analysis mainly comes from the pre-analytical phase.iQM enhanced specimen inspection capabilities and make up for the inability of traditional quality control to monitor the quality of specimens , enabling full-scale, real-time, and dynamic monitoring of each specimen , powerful error detection capabilities , and automatic error correction capabilities . Besides, automatic documentation saves staff much time.The system can effectively ensure the accuracy of blood gas test results, meet the quality requirements of related laws and regulations and related industry standards , and also can meet the clinical intended use , providing new ideas for POCT quality management and improvement.
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Objective To establish a candidate reference method for determination of serum glycated albumin based on isotope dilution liquid chromatography /tandem mass spectrometry(ID-LC/MS). Methods Establishment of a method.According to the Japan Society of Clinical Chemistry(JSCC) reference method,the serum albumin was firstly purified by SDS-PAGE and decomposed into amino acid fragments.It selected 2H and 13C respectively as internal standards of lysine and DOF-lysine and chose the lysine and DOF-Lysine as standard material.Then the lysine and DOF-lysine were determined according to peak area after the optimization of analysis conditions.The validity of reference method was verified by the glycated albumin standard material JCCRM611-1 of Japan check medical material institutions.The evaluation of precision depended on the determination of three different concentrations of mixed serum samples for three days.The patients'serum(35 specimens)were determined by this method and a routine test method, and then the correlation of measured value was confirmed.Results The total CV of JCCRM611-1 reference material were 3.2%,2.3% and 2.6%, which had the bias of +2.25%, +2.38%, -1.21% by the deviation values.The intra CV was 0.33%-2.53%,CV for between -run assays was 0.83%-1.32%,total CV ranged from 2.27% to 3.2%.Correlation coefficient of the mass spectrometry and routine enzymatic method is 0.993.Conclusions The ID-LC/MS method for the measurement of serum glycated albumin is precise and accurate.In addition,this method showed great correlation with routine enzymatic method.It can be proposed as a candidate reference method for the determination of serum glycated albumin in China.
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Diagnosis and treatment of diabetes mellitus depend on accurate monitor of blood glucose of laboratory.Glycated albumin,the short-term indicator of blood glucose control, has special advantage and role in the monitor of diabetes mellitus and has been payed more and more attention.The standardization work of determination of glycated albumin at home and abroad is still in the primary stage at present.The consistency and accuracy of measurement results for glycated albumin is needed to be solved urgently.
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Objective To establish the target measurement uncertainty(MU)of the routine coagulation assay according to the External Quality Assessment data(EQA)of routine coagulation assay. Methods Beijing Center for Clinical Laboratory(BCCL)established the target measurementuncertainty for routine coagulation assayswith the"up-down"methodon the basis of 93 clinical laboratoriesEQA datain BeijingThese assays includedActivated partial thromboplastine time(APTT), Fibrinogen(FBG), International Normalized Ratio(INR), Prothrombin time(PT), Thrombin time(TT)and D-dimer, Compared with CLIA′88,the proficiency of current coagulation assayswas observed.Results The MU of six routine coagulation assayscompared with CLIA ′88 showed that: The 90th percentile MU met the creteriain APTTof group B,FBG of group A&B&C,INR of group B and D-dimer of group B.The 75th percentile MU met the creteriainINR of group A&C,PT of group C.The medium met the creteriainAPTT of group A&C,PT of group A and INR of group D.Conclusions Target Measurement Uncertainty was establishedin routine coagulation assay by using EQA data only,whichcan simplify the procedure of determining MU and continuously update MU according to the frequency of EQA.It has good clinical practical value.However, the applicability of this method should also be considered.
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Accurate results in clinical laboratory are extremely important for patient safety.Quality control is the effective method to control the quality of testing process and ensure the patient safety.With the development of detection technology, the concept of quality control has changed.Clinical Laboratory Standards Institute(CLSI)has established a committee to formulate guidelines for quality control plan based on risk management in the laboratory, using the technology of risk management to develop individualized quality control plan.This article will introduce the understanding and practice of individualized quality control plan.