Reactivity versus reading time for ES33-MICT (A) and T24-MICT (B). Three serum samples, N (normal), C (cross-reactor), and P (positive), were added to five devices each for the ES33- and T24-MICTs. Reactivity was measured for each device in 5-min intervals. MAR value, the ratio of the RMU of test line divided by the RMU of control line; S/N, signal-to-noise ratio (the MAR value of the positive serum divided by the MAR value of the negative serum).