Initial reagent screening using the ECL assay format focused on interference from the matrix and soluble antigen (Figure ). The screening of labeled pairs using different assay formats used a more complex scoring function (Figure ). The parameters assessed in this scoring function included background signal, signal to noise, sensitivity, dynamic range, and soluble antigen interference. These parameters were assessed using 6 different assay formats and at two different anti-ID concentrations. A total score was calculated based on the listed criteria (Figure ).