Fig. 9.

Frequency of registrants over time in response to internet advertising according to patient-reported race (a), gender (b), education (c), and income (d). By time series regression analysis, a higher rate of increase was seen in white populations compared to African Americans (p<0.001) and college or higher educated populations compared to high school education or less (p<0.001). A marginally higher rate of recruitment was seen in females compared to males (p=0.043) and higher income individuals (p=0.048)