Participants
Children (ages 29 days to 17 years) with confirmed COVID-19 infection
prior to or during hospitalization (PCR, antigen, or IgG/IgM+) who
underwent chest X-ray between admission and 72 hours after
hospitalization were included in this sample. Chronic lung disease with
possible confounding radiological findings (bronchiolitis obliterans,
bronchopulmonary dysplasia, ciliary dyskinesia, tuberculosis, cystic
fibrosis, congenital pulmonary malformations, intestinal disease, among
others) was among the exclusion criteria. Also, chest-radiographs that
could not be retrieved from the PACS system (Picture Achieving
communication system) or that could not be found, were excluded from the
reading list. For more information about data analysis X-ray selection
flowchart, please see supplementary appendix 1.