Lab Med Online.  2022 Jul;12(3):169-174. 10.47429/lmo.2022.12.3.169.

Performance Evaluation of the AllCheck hCG Card Point-of-Care Device and Method Comparison with the Alere hCG Cassette Assay for Pregnancy Test

• Lee KS
• Kim BH
• Ahn HJ
• Kim JH
• Roh KH
• Yoo J

• KMID: 2538601
• DOI: http://doi.org/10.47429/lmo.2022.12.3.169

Abstract

Background
Immunochromatographic point-of-care (POC) devices ae widely used by laboratories and lay users for urinary human chorionic gonadotropin (hCG) detection. Performance evaluation of pregnancy POC devices is rarely published. We performed an analytical and clinical validation of the newly introduced AllCheck hCG Card assay and compared it with the Alere hCG Cassette comparative assay.
Methods
The analytical performance of the assay was evaluated using an international standard material for hCG, as per the protocol recommended in the Clinical and Laboratory Standards Institute (CLSI) guideline. Clinical validation and comparison study with the comparative method were performed with remnant urine samples from pregnant and non-pregnant women.
Results
Probit analysis showed an analytical sensitivity of 15.82 mIU/mL. The precision of the assay was validated at a threshold of 30%. Cross-reactivity with luteinizing hormone, follicle-stimulating hormone, and thyroid-stimulating hormone was not observed. Comparison with the comparative assay showed a negative percent agreement of 100.0% (95% confidence interval [CI]: 92.9%-100.0%) and a positive percent agreement of 96.4% (95% CI: 89.9%-98.8%). Cohen’s kappa value was 0.952 (95% CI: 0.899-1.000).
Conclusions
Overall, we validated the performance of the urine hCG POC device and suggest that probit regression is suitable for qualitative tests other than molecular tests. The AllCheck hCG Card device satisfied the demanding standards suggested by the CLSI guideline and was suitable for clinical use.

Keyword

Analytical sensitivity; Probit regression; Pregnancy test; Human chorionic gonadotropin; Precision; Qualitative test

Figure

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  Fig. 1 Imprecision curve with probabilities of positive result and hCG concentrations (25.0, 20.0, 17.5, 15.0, 12.5, and 10.0 mIU/mL).

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