Randomization
The unit of randomization was the ED. The strategy (control/intervention) applied during the first period was assigned using a balanced block randomization process with stratification based on ED flow and, for feasibility concerns, whether the ED had a SARS-CoV-2 screening device (block size of 2 to 6). The alternative strategy was applied during the second period after a minimum 1-day washout interval. The allocation schedule was computer generated in SAS by an independent statistician.The duration of each period was a minimum of 1 month with the possibility of a 15-day extension for the interested EDs, retaining similar durations for the same center in each period.The patients and teams could not be masked to allocation due to the nature of the intervention.