The participants were medical students enrolled at the University of Heidelberg. The medical degree program lasts a total of 6 years, the first five of which consist of theoretical and practical courses. State examinations are held after 2 years and after 5 years. After the second state examination, students complete their practical year, which consists of three tertials of surgery, internal medicine, and an elective subject.

There were two groups of participants: First, medical students in their final year of study, the so-called practical year or internship year, were included. In Germany, medical studies are lasting 6 years of which the first 5 years are mainly theoretical in content. The last year after the written final exam is practical. These final year students passed their written state examination. Afterwards they have to spend one of three tertials in the surgery department at the time of the study. The three tertials consist of a mandatory tertial in internal medicine and surgery, as well as an elective subject. Each tertial lasts 16 weeks. These students will have to pass an oral exam at the end of the third tertial (n before = 38, n after = 41). The second group of participants were medical students in their fourth year of study (n before = 38, n after = 29) during the surgical training block. Participation in this study was voluntary and anonymous.

During the surgical tertial in the final year of training, medical students must gain experience in general surgery and visceral surgery for at least 8 weeks up to 16 weeks. Other possible surgical departments like vascular or trauma surgery can be chosen too for at least 4 weeks up to 8 weeks. During this time, students take part in ward rounds, support the surgeons during an operation, learn how to write medical letters, and present patients in the surgery planning meeting.

Whereas, in the fourth year of medical training at the University of Heidelberg, students complete weekly courses in vascular surgery, cardiac surgery, thoracic surgery, orthopedics and trauma surgery, visceral surgery, urology, and emergency medicine. During this time, students learn practical skills such as suturing porcine skin or surgical knotting. Anamnesis interviews with subsequent diagnosis are learnt with the help of acting patients. Emergency medical treatment procedures are also learnt on simulation dolls. In the subject “clinical-pathological conference,” fourth year medical students learn to link surgical clinical pictures with histological images and radiological images.

The “Radisurg ” seminar began with a knowledge test (n = 32 points maximum) including surgical knowledge questions from different subject areas with reference to radiological imaging (e.g., hollow organ perforation, hepatocellular carcinoma, perforated cholecystitis) with resulting therapies. The questions included both KPrim-choice questions and single-choice questions. The response time per question was 90 s. Afterwards specialists from the departments of surgery and radiology discussed requested basic surgical topics in detail, including operation photos, operation videos, and the corresponding imaging (CT, MRI, angiography, X-ray, ultrasound). The session lasted 60 min, followed by the same surgical knowledge questionnaire that was answered in the beginning. After the knowledge test, nine evaluation questions followed. The evaluation questions were analyzed using a 5-point Likert scale [13]. A Likert scale consists of five statements that all measure the same characteristic. This allows the assessment of agreement or disagreement; for example, a Likert score of 1 means that the participant strongly agrees or strongly disagrees. If a Likert score of 1 means that the participant strongly agrees, then a Likert score of 2 means that the participant agrees less than with Likert scale 1, but more than with Likert scale 3. Students who did not respond to the questionnaires were not included in the study.

Statistical tests were carried out using Excel™ 2019, SPSS™ (version 29), and GraphPadPrism™ (version 9). Results of the knowledge questions were reported as box plots with 25th–75th percent quartiles with interquartile range and minimum/maximum. To calculate differences between independent samples, the Mann–Whitney U test was assessed. The chi-square test and Fisher’s exact test were performed for evaluation questions. A p -value ≤ 0.05 was considered significant. Percentages of numerical Likert scale of 1 and 2 were added together to receive a statement about the positive evaluations. Congruently, to get a statement about the negative ratings, the percentages of the scale of 4 and 5 were summed up accordingly. Because some Likert scale ranges were not chosen by the students, some evaluation questions could not be calculated.

Ethics approval was granted by the University of Heidelberg (S-334/2023). This study was performed in line with the principles of the Declaration of Helsinki. Written informed consent was obtained from all individual participants included in the study.