Fig. 4

a Resection margins. Distribution of minimal resection margins in mm comparing residents to specialists and its p-value (Mann–Whitney U test). b Range of Resection Margins. Relationship between minimum and maximum resection margins in mm compare between residents and specialists. c Actual margins. Percentage of resection margins according to categories (positive, close, clear, and excessive margin) comparing residents to specialists. (d) Self-Assessed Margins. Percentage of self-assessed margins according to a 4-point Likert scale (1 = disagree to 4 = agree) comparing residents to specialists. e Resection-Time. Resection time in minutes comparing residents to specialists and its p-value (t-test). a, b, e Plots using boxplots and violin plots. Black dots are outliers, and the red dot is the mean X-axis (a, b, e)