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Analytical performance evaluation of the i-STAT Total β-human chorionic gonadotropin immunoassay. Clin Chim Acta 2015 Jun 15;446:165-70

Date

04/29/2015

Pubmed ID

25916696

DOI

10.1016/j.cca.2015.04.025

Scopus ID

2-s2.0-84928802805 (requires institutional sign-in at Scopus site)   17 Citations

Abstract

BACKGROUND: 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.

METHODS: 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.

RESULTS: Imprecision was highest with whole blood (CV = 16.0% and 6.7% at 10 and 1184 IU/l, respectively) and lowest in serum (CV = 8.1% and 4.3% at 11 and 1305 IU/l, respectively). The limits-of-quantitation were 8 and <5 IU/l for whole blood and both plasma and serum, respectively. The assay was linear between 5 and 2000 IU/l in all sample types (R(2) ≥ 0.998). i-STAT results agreed most closely with the Architect Total β-hCG assay and with greater differences observed with Beckman DxI Total βhCG and Roche Cobas e601 hCG+β assays (mean differences across all sample types were 9.3% and 12.3%, respectively). A high-dose hook effect was observed at concentrations > 400,000 IU/l. Accuracy was achieved in samples diluted with serum but not saline.

CONCLUSIONS: The i-STAT Total β-hCG test demonstrates acceptable performance for quantifying hCG in whole blood, plasma and serum.

Author List

Sowder AM, Yarbrough ML, Nerenz RD, Mitsios JV, Mortensen R, Gronowski AM, Grenache DG

Author

Robert D. Nerenz PhD Associate Professor in the Pathology and Laboratory Medicine department at Medical College of Wisconsin




MESH terms used to index this publication - Major topics in bold

Adult
Calibration
Chorionic Gonadotropin
Female
Humans
Immunoassay
Limit of Detection
Point-of-Care Systems
Pregnancy Tests
Reference Values
Reproducibility of Results