Coronary artery calcium to improve the efficiency of randomized controlled trials in primary cardiovascular prevention - Cainzos-Achirica, Miguel; Bittencourt, Márcio Sommer; Osei, Albert D; Haque, Wagas; Bhatt, Deepak L; Blumenthal, Roger S; Blankstein, Ron; Ray, Kausik K; Blaha, Michael J; Nasir, Khurram (JACC: Cardiovascular Imaging, 2021)