Prevalence of control groups in cardiovascular clinical trials: An analysis of ClinicalTrials.gov from 2009 through 2019

Clinical trials provide the foundational evidence that guide many patient-facing decisions; however, the therapeutic effect and safety of an intervention is best evaluated when compared to a control group. We used ClinicalTrials.gov to describe the proportion of registered Phase III and IV cardiovascular clinical trials that contain a control group from 2009 through 2019. Of 1,677 registered Phase III and IV cardiovascular clinical trials, 81.2% contain a control group, and the annual prevalence remained unchanged between 2009 and 2019.