Fig. 2

Arrangement of the three target drugs in the drug rack area. A single-type drug and a double-type drug in groups A and B (likewise, those in groups C and D) have the same efficacy, the same ingredient quantity (number part), and the same position. The single-type drugs in groups A and C (likewise, double-type drugs in groups B and D) are the same; however, they are shifted six rows in the right and left directions. The double-type drugs in groups E, F, and G are the same and they have the same arrangement, while non-target drugs in groups F and G are located on the right side of the target drugs. There are no drug photographs in group G, and grey illustrations are displayed instead