Abstract: A method of evaluating a POC system that includes loading a first LQC fluid onto the testing chamber and measuring the first LQC fluid with the sensor to obtain a first actual measurement, where the first LQC fluid can comprise a first known concentration of an analyte. The method also includes loading a second LQC fluid, having a second known concentration of the at least one analyte, into the testing chamber and measuring the second LQC fluid with the sensor to obtain a second actual measurement. The known concentrations are evaluated against the actual measurements to determine difference values. The values are compared against expected LQC values to determine if the cartridge, the cartridge manufacturing lot, the POC system, or the user proficiency are outside quality control expectations.