The original studies were performed by adding increasing concentrations of purified hCGβcf to a urine sample obtained from a pregnant woman. The problem with this approach is that the relative abundance of hCG, hCGβcf and other hCG variants in the urine that may affect device performance vary between women. A standardized method, using defined concentrations of hCG, is needed to evaluate the performance of currently available devices.
In a recent publication, we describe a screening method that can be easily used to examine the effect of hCGβcf and have used this method to test eleven POC hospital urine hCG devices.
Examination of eleven hospital hCG devices for false negative results
Source: The Pregnancy Lab