Interlaboratory Oral Anticoagulant Quality Assessment by the Netherlands Federation of Thrombosis Services

The 50 laboratories of the Netherlands Federation of Thrombosis Services have participated since 1974 in a voluntary external and internal quality control program. The external program comprises a monthly distribution to the member laboratories of a series of artificially prepared control blood samples, two of which are identical. The overall variation of the coagulation times found were 10% (CV) in 1974 and 8% (CV) in 1975 and 1976. Performance improved rather abruptly at the beginning of 1975, after the application of a tight methodological standardization and improvement by the manufacturer of the thromboplastin preparation (Thrombotest) used by the great majority of the laboratories involved. The main source of variation wasfound to be random error in the Thrombotest determination, approximating 6%. interbatch variation of Thrombotest and inter-aliquot variation of control blood samples both do amount to approximately 3%.

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Interlaboratory Oral Anticoagulant Quality Assessment by the Netherlands Federation of Thrombosis Services

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649260 ◽

1977 ◽

Vol 37 (03) ◽

pp. 509-522 ◽

Cited By ~ 7

Author(s):

C. A van Dijk-Wierda ◽

J Hermans ◽

E. A Loeliger ◽

J Roos

Keyword(s):

The Netherlands ◽

Control Program ◽

Great Majority ◽

Internal Quality ◽

Lower Sensitivity ◽

Reference Laboratory ◽

Quality Control Program ◽

Blood Samples ◽

Monthly Distribution ◽

External Program

SummaryThe 50 laboratories of the Netherlands Federation of Thrombosis Services, covering a population of 9 million and responsible for the laboratory control of approximately 150,000 patients under oral anticoagulation, have participated since 1974 in a voluntary external and internal quality control program. The external program comprises a monthly distribution to the member laboratories of a series of artificially prepared control blood samples, two of which are identical. The overall variation of the coagulation times found were 10% (CV) in 1974 and 8% (CV) in 1975. Performance improved rather abruptly at the beginning of 1975, after the application of a tight methodological standardization and improvement by the manufacturer of the thromboplastin preparation (Thrombotest) used by the great majority of the laboratories involved. The main source of variation was found to be random error in the Thrombotest determination, approximating 6%. Interbatch variation of Thrombotest and inter-aliquot variation of control blood samples both do amount to approximately 3% (CV). In terms of rabbit tissue thromboplastins, which have a lower sensitivity than Thrombotest (i. e., a flatter slope of the correlation between the PT and the anticoagulant effect), the total variation in the performance of the Dutch laboratories is 2.2-5.6% (CV), which is unusually low. The main reason for this is the fact that the laboratories can rely not only on the services of the manufacturer but also on a central information office and a reference laboratory responsible for the preparation of the control blood as well as the standardization (calibration) of thromboplastin.

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A coupled external/internal quality control program for clinical laboratories in the netherlands

Clinica Chimica Acta ◽

10.1016/0009-8981(80)90446-5 ◽

1980 ◽

Vol 107 (3) ◽

pp. 185-201 ◽

Cited By ~ 10

Author(s):

Rob T.P. Jansen ◽

Ad P. Jansen

Keyword(s):

Quality Control ◽

The Netherlands ◽

Control Program ◽

Internal Quality Control ◽

Internal Quality ◽

Quality Control Program ◽

Clinical Laboratories

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Standards versus Standardised Methods in Enzyme Assay

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456328302000108 ◽

1983 ◽

Vol 20 (1) ◽

pp. 52-59 ◽

Cited By ~ 15

Author(s):

R T P Jansen ◽

A P Jansen

Keyword(s):

Quality Control ◽

Alkaline Phosphatase ◽

Creatine Kinase ◽

Lactate Dehydrogenase ◽

Alanine Aminotransferase ◽

Enzyme Assay ◽

Control Program ◽

Internal Quality ◽

Quality Control Program ◽

Control Serum

In a trial of the Netherlands coupled external/internal quality control program a control serum and an enzyme standard were analysed over a period of eight weeks, five times each week. Five enzymes were determined: alkaline phosphatase, creatine kinase, lactate dehydrogenase, alanine aminotransferase, and γ-glutamyltransferase. The measured values in the serum were converted to the standards. Those laboratories using the recommended methods also submitted their non-transformed serum values. The following standardisation techniques have been compared: ( a) no standardisation of methodology but use of enzyme standards; ( b) standardisation of methodology; ( c) standardisation of methodology combined with use of an enzyme standard. Results were submitted to analysis of variance. Standardisation of methodology did not yield smaller interlaboratory variation than the standardisation with enzyme standards. In this trial a combination of both standardisation techniques yielded generally better results. Results for γ-glutamyltransferase indicate that standardisation of substrate may be necessary apart from the use of an enzyme standard. The preparation of stable enzyme standards is stressed.

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Variation in 1(3S) and 2(2S) rejections incidence in internal quality control program on using 20 reading mean and SD of different periods

International Journal of Biomedical and Advance Research ◽

10.7439/ijbar.v7i2.2690 ◽

2016 ◽

Vol 7 (2) ◽

pp. 48

Author(s):

Khushbu Suryaprakash Soni ◽

Riddhiben Rajendrakumar Patel ◽

Shailesh Manubhai Patel ◽

Sarita Jagadishbhai Mangukia

Keyword(s):

Quality Control ◽

Control Program ◽

Internal Quality Control ◽

Internal Quality ◽

Quality Control Program

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ARIC Hemostasis Study - III. Ouality Control

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649633 ◽

1993 ◽

Vol 70 (04) ◽

pp. 588-594 ◽

Cited By ~ 16

Author(s):

Lloyd E Chambless ◽

Robert McMahon ◽

Andrea Finch ◽

Paul Sorlie ◽

Gerardo Heiss ◽

...

Keyword(s):

Quality Control ◽

Control Program ◽

Internal Quality Control ◽

Factor Vii ◽

Quality Assurance Program ◽

Internal Quality ◽

Blood Collection ◽

Quality Control Program ◽

Atherosclerosis Risk In Communities ◽

Field Center

SummaryMethods and results from the quality assurance program of the Atherosclerosis Risk in Communities (ARIC) Study regarding hemostasis variables are presented, following up previous reports in this journal on standardized procedures for blood collection and processing (7) and an organized plan for the performance of those procedures (8). Efforts were made to control for and assess all sources of variability, from venipuncture to laboratory analysis, including also local field center processing and sample shipping. The quality control program included (a) a standardized protocol for blood collection and processing; (b) training, certification, and annual recertification of field center personnel for blood collection and processing; (c) monitoring of fasting times, phlebotomy times, processing times, and shipping problems; (d) hemostatic laboratory internal quality control; (e) a replicate blood sample program; (f) an intraindividual variability study; and (g) continual monitoring of quality control and study participants’ data. This paper focused on items (c), (d), and (e). Measures of Variation, generally Standard deviations and coefficients of Variation, are estimated for replicate blood sampling and internal quality control data, for activated partial thromboplastin time, fibrinogen, factor VII and VIII activity, von Willebrand factor, antithrombin-III, and protein C. The results demonstrate that it is possible to reliably measure these hemostatic variables in a large multicenter study.

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Comparison of Routine Analytical Methods in the Netherlands for Seven Serum Constituents Using Pattern Recognition

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456328302000107 ◽

1983 ◽

Vol 20 (1) ◽

pp. 41-51 ◽

Cited By ~ 3

Author(s):

Rob T P Jansen

Keyword(s):

Pattern Recognition ◽

The Netherlands ◽

Calcium Chloride ◽

Analytical Method ◽

Analytical Methods ◽

Inorganic Phosphate ◽

Dimensional Space ◽

Control Program ◽

Internal Quality ◽

Quality Control Program

Routine analytical methods for seven serum analytes (calcium, chloride, cholesterol, glucose, inorganic phosphate, urate, and urea) are assessed using data from the Netherlands coupled external/internal quality control program. From the results of a trial each method can be described by four features: measures of bias, between-day precision, tendency to give erroneous results, interlaboratory variance. These four features of each trial determine a vectorpoint in the four-dimensional space for a particular method. From 12 trials a maximum of 12 vectorpoints per analytical method was obtained. Pattern recognition techniques allowed the detection of clusters of vectorpoints. Analytical methods having vectorpoints classified in different clusters perform differently. The mean feature values of the vectorpoints forming a cluster determine the quality of that cluster. A weighting procedure reveals the importance of the respective features for discriminating the clusters. For all of the seven analytes, clusters of vectorpoints were found. Different features appeared to contain discriminatory power for different analytes. For six analytes (calcium, chloride, cholesterol, glucose, inorganic phosphate, and urea) an analytical method was found to classify predominantly in the qualitative best cluster. One analytical method for the determination of chloride and one for glucose, inorganic phosphate, and urea did not cluster at all.

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