When looking at how participation rates changed with time, we found that the rate of white participants decreased at a rate of 0.51% per year (r = -0.23, p < 0.01) (Figure 3B). This decrease in participation was accompanied by an increase in the rate of Asian participants by a rate of 1.07% per year (r = 0.279, p < 0.01) (Figure 3C). However, the rate of African American participants decreased at a rate of -0.30% per year (r = -0.34, p < 0.001) (Figure 3D). The rates of participation among Hispanics (r = -0.01, p = 0.97), the other category (r = -0.04,p = 0.65), and the unknown category (r = 0.14, p = 0.55) did not change with time (Figure 3E, 3F, 3G), although we did not have enough studies report Hispanic demographics to draw meaningful conclusions about their representation.