Fig. 3

Subgroup analysis comparing pre- and post-course self-assessment (Δ self-assessment). A subgroup (sex: male vs. female) analysis for differences in Δ self-assessment, B) subgroup (age: 19–22 years vs. 23–29 years vs. ≥ 30 years) analysis for differences in Δ self-assessment, C) subgroup (prior surgical experience: with vs. without surgical experience) analysis for differences in Δ self-assessment, D) analysis for differences in Δ self-assessment comparing COV-19 vs. postCOV-19. Data are presented as mean and compared using Student’s t-test or ANOVA. A p-value less than 0.05 was considered statistically significant. Significance is indicated by the following symbols: * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.00001, ns = not significant. COV-19 = cohort of summer semester 2021 (full COVID-19 restrictions), postCOV-19 = cohort of winter semester 2021/2022 (reduced COVID-19 restrictions)