Clarifications of Terms and for Interpreting Incidence Rate Ratios

In the Original Investigation, “Association of the Timing of School Closings and Behavioral Changes With the Evolution of the Coronavirus Disease 2019 Pandemic in the US,” published online first on February 22, 2021, in JAMA Pediatrics, there were errors in the text for description of the incidence rate ratios (IRRs). In the Abstract and main text, “delay of 1 day” and “day of delay” have been corrected to “advance of 1 day” and “each day earlier.” The term “days since” has been corrected to “each day earlier” in the text and defined in the legend of the Table as “how much earlier in the pandemic either school closures, gathering bans, or work reductions happened. Each 1-unit increase in a ‘days since’ variable represents 1 day earlier that the change happened.” These corrections do not affect any of the IRRs or other data. The article has been corrected online.