Table 1.

Search strategy criteria

Inclusion criteria 1 Study population: hyperinflammatory syndrome meeting the case definitions of PIMS-TS [19] or MIS(-C) [20, 21] in children (0–21 years of age) with a temporal association with confirmed or probable COVID-19 2 Outcome: clinical, epidemiological, and immunological descriptions; therapeutic management and clinical effect; and prognosis of individuals or cohorts of patients. 3 Types of study designs: RCT, observational studies, case-control studies, cross-sectional studies, case reports, and case series Exclusion criteria 1 Studies on adult patients with SARS-CoV-2 infection and/or SARS-CoV-2 associated hyperinflammatory syndromes 2 Studies on pediatric patients with other coronavirus infections (SARS-CoV-1 and Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection or other respiratory infections. 3 Studies with incomplete or lacking necessary data 4 Duplicate studies 5 Studies without accessible full-text versions 6 Studies not in English language