Error in Text and Figure Axis: In the Special Communication entitled “Evaluating the Risks of Clinical Research,” published in the October 6, 2010, issue of JAMA (2010;304[13]:1472-1479), an error appeared in the text and figures. On page 1475, column 3, lines 7 and 8 in the first full paragraph, likelihoods should have been “less than 1 per 100 million.” In Figure 1 and Figure 2 on pages 1476 and 1477, values on the y-axis should have been “105, 104, 103, 102, 10, 1, 10−1, 10−2, and 10−3.” This article has been corrected online.