Analytical performance evaluation of the i-STAT Total β-human chorionic gonadotropin immunoassay

• Published in: Clinica chimica acta 2015-06, Vol.446, p.165-170
• Main Authors: Sowder, Aleksandra M., Yarbrough, Melanie L., Nerenz, Robert D., Mitsios, John V., Mortensen, Rachel, Gronowski, Ann M., Grenache, David G.
• Format: Article
• Language: English
• Subjects: Adult; Calibration; Chorionic Gonadotropin - blood; Female; Human chorionic gonadotropin; Humans; Immunoassay - standards; Limit of Detection; Point-of-care; Point-of-Care Systems; Pregnancy test; Pregnancy Tests - standards; Quantitative; Reference Values; Reproducibility of Results; Whole blood
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/j.cca.2015.04.025

The ability to perform quantitative hCG testing in whole blood at the point-of-care is desirable. The purpose of this study was to perform an analytical validation of the Abbott i-STAT Total β-hCG test. Whole blood, plasma, and serum samples were prepared by the addition of hCG and were used to evaluate precision, linearity, analytical sensitivity, accuracy, the high-dose hook effect, and dilution recovery. Imprecision was highest with whole blood (CV=16.0% and 6.7% at 10 and 1184IU/l, respectively) and lowest in serum (CV=8.1% and 4.3% at 11 and 1305IU/l, respectively). The limits-of-quantitation were 8 and 400,000IU/l. Accuracy was achieved in samples diluted with serum but not saline. The i-STAT Total β-hCG test demonstrates acceptable performance for quantifying hCG in whole blood, plasma and serum. •Analytical performance of a point-of-care blood test for hCG was determined.•Imprecision, accuracy, and linearity were within allowable error limits.•A high-dose hook effect was observed at an hCG concentration >400,000 IU/L.•hCG-negative serum can be used to dilute serum samples with hCG concentration >2000 IU/L.