A device for use with a fluid sample, the device comprising: a conjugate pad including conjugates for a target analyte; and a test grid including a plurality of zones in a two-dimensional grid, the test grid including: a first test zone in the plurality of zones including at least one of first immobilized antibodies or first immobilized antigens to attach to the target analyte labeled with a first conjugate of the conjugates; a second test zone in the plurality of zones including at least one of second immobilized antibodies or second immobilized antigens to attach to the target analyte labeled with a second conjugate of the conjugates; a control zone in the plurality of zones including at least one of third immobilized antibodies or third immobilized antigens to attach to conjugates not bound to the target analyte; and a blank zone in the plurality of zones that does not include immobilized antibodies or immobilized antigens; wherein a location of the first test zone and the second test zone within the test grid is according to a test grid pattern that is related to identifying information of the device, wherein in the test grid pattern the test zones, control zone and blank zone are randomly distributed such that results appear random to a user. a conjugate pad including conjugates for a target analyte; and a test grid including a plurality of zones in a two-dimensional grid, the test grid including: a first test zone in the plurality of zones including at least one of first immobilized antibodies or first immobilized antigens to attach to the target analyte labeled with a first conjugate of the conjugates; a second test zone in the plurality of zones including at least one of second immobilized antibodies or second immobilized antigens to attach to the target analyte labeled with a second conjugate of the conjugates; a control zone in the plurality of zones including at least one of third immobilized antibodies or third immobilized antigens to attach to conjugates not bound to the target analyte; and a blank zone in the plurality of zones that does not include immobilized antibodies or immobilized antigens; a first test zone in the plurality of zones including at least one of first immobilized antibodies or first immobilized antigens to attach to the target analyte labeled with a first conjugate of the conjugates; a second test zone in the plurality of zones including at least one of second immobilized antibodies or second immobilized antigens to attach to the target analyte labeled with a second conjugate of the conjugates; a control zone in the plurality of zones including at least one of third immobilized antibodies or third immobilized antigens to attach to conjugates not bound to the target analyte; and a blank zone in the plurality of zones that does not include immobilized antibodies or immobilized antigens; wherein a location of the first test zone and the second test zone within the test grid is according to a test grid pattern that is related to identifying information of the device, wherein in the test grid pattern the test zones, control zone and blank zone are randomly distributed such that results appear random to a user. <EOS>