In the Original Investigation entitled “Calcium Density of Coronary Artery Plaque and Risk of Incident Cardiovascular Events” published in the January 15, 2014, issue of JAMA (2014;311[3]:271-278. doi:10.1001/jama.2013.282535), values for the absolute risk decrease of the density scores for coronary heart disease (CHD) and for cardiovascular disease (CVD) were incorrect. In the Results section of both the abstract and the article (paragraph 6), the score for CHD should be 2.0 per 1000 person-years and the score for CVD should be 3.4 per 1000 person-years. This article was corrected online.