The Original Investigation titled “Effect of a Restrictive vs Liberal Blood Transfusion Strategy on Major Cardiovascular Events Among Patients With Acute Myocardial Infarction and Anemia: The REALITY Randomized Clinical Trial” published February 9, 2021, was corrected to fix the number of events for the primary outcome. Calculation of the primary composite outcome had mistakenly included heart failure events as a component, and the date of consent withdrawal was recorded incorrectly for 4 patients (before 30 days rather than after 30 days). Thus, as specified in the protocol and statistical analysis plan, they should have been considered missing, but had been coded as “no event.” After correction, the number of events for the primary outcome is slightly lower than in the original analysis (29 vs 36 for the restrictive transfusion group and 36 vs 45 for the liberal group). This change does not impact the main conclusion: the restrictive strategy resulted in a noninferior rate of major adverse cardiovascular events after 30 days compared with the liberal strategy. This article has been corrected online; a letter of explanation appears in this issue.