Reproducibility of relative hyperreactivity to epinephrine over months to years. Fifteen subjects in the reproducibility study had had PRP aggregometry at 0.4 μM epinephrine performed in the past. The older data are shown as open triangles and plotted on the corresponding scatter plot from Figure 3A (same subject numbering). Values above/below the data points indicate the number of months (mean = 19 months) elapsed between the first result and subsequent (RS) results.