The number of patients treated with roxifiban without DDAB testing as an exclusion criterion is indicated (no DDAB test). After implementation of a DDAB antibody ELISA, patients were excluded from the studies based on a pre-existing or developing DDAB concentration (DDAB test). The frequency of thrombocytopenia in both groups is indicated. The results were analyzed using a 2-sided Fisher exact test. A statistically significant reduction in the frequency of thrombocytopenia (P = .0007) was observed using the DDAB ELISA as an exclusion criterion.