Autor:innen:
M. Zuchowski (Berlin, DE)
F. Mockenhaupt (Berlin, DE)
J. Maksoud (Berlin, DE)
U. Schweitzer (Berlin, DE)
K. Kappert (Berlin, DE)
A. Jahic (Berlin, DE)
Introduction:
Confirming relevant performance characteristics (i.e. verification) of laboratory systems for their implementation in routine diagnostics is crucial for quality assurance in clinical laboratory. Thereby, a diagnostic laboratory method or analyzer is proven being suitable for fulfilling tasks with far-reaching decisions regarding patients' health as well as economic processes in clinical laboratory. Therefore, a variety of aspects must be taken into account during the practical implementation and laboratory system verification as well as transfer into clinical routine diagnostics.
Aims and Methods:
The main goal of the study was to re-evaluate the analytical performance of the cobas pure integrated solutions system under routine laboratory conditions. Measurements were performed comparing the cobas® 6000 routine clinical chemistry analyzer with the novel cobas pure integrated solutions system. The intra-day imprecision for the cobas pure integrated solutions system was determined by measuring quality control (QC) samples.
Results:
In total, 145 patient samples for comparative measurements on both clinical chemistry systems and six QC samples for intra-day imprecision analyzes on cobas pure integrated solutions system were included in the study. Six selected analytes each representing one of the six different test methods such as potentiometry (sodium, Na; N=24+1), turbidimetry (C-reactive protein, CrP; N=25+1), heterogeneous immunoassay (thyroid-stimulating hormone, TSH; N=23+1), IFCC standardized kinetic method (alanine aminotransferase, ALAT; N=23+1), colorimetry (albumin, ALB; N=25+1) as well as IFCC standardized colorimetry (alcaline phosphatase, AP; N=25+1) were assessed. The cobas pure integrated solutions system showed an average negative bias of 4.50 mmol/L for Na, 3.84 mg/L for CrP, 0.08 mU/L for TSH, 3.89 mU/L for ALAT, 6.55 U/L for AP and an average positive bias of 0.28 g/L for ALB. The corresponding coefficients of correlation (R2) ranged from 0.999 (Na, CrP, TSH, AP and ALB) to 1.000 (ALAT) suggesting an excellent statistical correlation between the two laboratory systems tested. Repeated measurements of QC samples on the cobas pure integrated solutions system exhibited an intra-day imprecision of 0.47 % for Na (mean = 145.79 mmol/L), 0.45 % for CrP (mean = 41.28 mg/L), 1.14 % for TSH (mean = 1.78 mU/L), 0.44 % for ALAT (mean = 130.70 U/L), 0.43 % for ALB (mean = 34.52 g/L) and 0.29 % for AP (mean = 247.25 U/L) complying with acceptance criteria.
Conclusion:
The results obtained by comparative analyses as well as imprecision data suggest suitability of the cobas pure integrated solutions system for routine clinical laboratory diagnostics.