2.3 Study population
Files of children evaluated for “acute asthma”, “bronchospasm”, or “wheezing bronchitis” from January 1st, 2015 to December 31st, 2020, in the PED of Sant’Orsola University Hospital of Bologna were retrospectively revised. The triage acuity, defined by a 4-colour scale and divided into low-priority (white and green) and high-priority (yellow and red) codes, and the outcome (discharge, admission to the Short Stay Observation Unit, SSOU, or to the ward) were also considered.