Additional file 1: Figure S1. Duration of symptoms at presentation, cohort 2019 versus 2020. Table S1. Comparison of patients with uncomplicated appendicitis for 2019 pre-COVID cohort vs. 2020 COVID cohort. Table S2. Comparison of patients with complicated appendicitis and with symptoms for more than 24 h, 2019 pre-COVID cohort versus 2020 COVID cohort. Table S3. Comparison of patients with an age of 60 years or higher of the 2019 pre-COVID cohort and 2020 COVID cohort. Table S4. Comparison of conservatively treated patients with appendicitis, 2019 pre-COVID cohort versus 2020 COVID cohort. Table S5. Comparison of conservatively treated patients by final (imaging) diagnosis and imaging modality, 2019 pre-COVID cohort versus 2020 COVID cohort. Table S6. COVID-19 positive appendicitis patients.