Study cohort

In total, voluntary questionnaires from the new case-and competency-based course from n = 235 students were received, resulting in a response rate of 93.3%. Students had a mean age of 23.5 ± 2.6 years, while n = 64 (27.2%) students were male, n = 170 (72.3%) were female, n = 1 (0.4%) student did not report gender, and none identified as diverse. Most of the students (n = 188, 80.0%) had no prior education or academic degree before entering medical studies, while n = 40 (17.0%) had completed prior education (n = 24, 10.2% nursing or medical assistant; n = 11, 4.7% paramedics, n = 7, 3.0% other) and n = 7 (3.0%) had received an academic degree. In total, n = 22 (9.4%) datasets of voluntary questionnaires before and/or after the course were (partially) incomplete and thus excluded from paired statistical analysis.

Perceived importance of training in abdominal radiology

First, we evaluated how students judged the importance of receiving teaching in abdominal radiology during their medical studies. Before receiving any teaching, students strongly agreed, with a mean ± SD score of 9.0 ± 1.3, that knowledge of abdominal radiology is important for the profession of a medical doctor independent of later specialization (Fig. 2a). In this context, after the course, students strongly agreed with a score of 8.2 ± 1.7 that the learned content will be beneficial for their future practice (Fig. 2b).

Fig. 2

Perceived importance of abdominal radiology teaching. Rating (0—strongly disagree to 10—strongly agree) of medical students. a Before the course regarding the importance of learning about abdominal radiology and (b) after the course regarding the importance of learned content for the future medical career

Thus, receiving dedicated radiological training is very important to today’s medical students, and the new case- and competency-based teaching yields a high agreement in perceived importance.

Perceived gain of competence in abdominal radiology

Second, we evaluated the perceived gain in competence of medical students in choosing an imaging modality, as well as image description and analysis, for common abdominal diseases. Detailed numbers of all tested items can be found in Table 1. Briefly, the perceived gain in competence significantly (all p-values < 0.001) improved in (1) knowledge of imaging modalities for abdominal imaging (Cohen’s d = 0.79, Fig. 3a), (2) reasoned decision-making for choosing imaging modalities (d = 0.95, Fig. 3b), (3) locating abdominal organs (d = 0.27, Fig. 3c), (4) assessing abdominal pathologies in ultrasound (d = 0.62, Fig. 3d), (5) X-ray (d = 0.80, Fig. 3e), (6) CT (d = 0.86, Fig. 3f), and (7) MRI (d = 0.92, Fig. 3g). The strongest effects of the course were seen for reasoned decision-making in choosing an imaging modality in a given clinical scenario (d = 0.95), and in image interpretation of more complex, cross-sectional modalities like CT and MRI with effect sizes of d = 0.86 and d = 0.92, respectively.

Table 1 Perceived gain in competenceFig. 3

Perceived gain in competence by case- and competency-based learning. Rating (0—strongly disagree to 10—strongly agree) of medical students before and after the course of the perceived competence in (a) the knowledge of imaging modalities available for abdominal imaging, (b) reasoned decision-making to choose an imaging modality in a defined clinical scenario, (c) locating abdominal organs in abdominal imaging datasets; and description and assessment of common abdominal pathologies in (d) ultrasound, (e) X-ray, (f) CT or (g) MRI datasets. ***p < 0.001

Fig. 4

Perceived fun during case- and competency-based learning. Rating (0—strongly disagree to 10—strongly agree) of medical students after the course regarding (a) the interest and (b) the fun during case-based work. c Medical students also rated if the new case- and competency-based format was more fun compared to traditional lectures and seminars

Fig. 5

Students’ pedagogical perceptions of the new case- and competency-based teaching approach. Rating (0—strongly disagree to 10—strongly agree) of medical students after the course regarding the additional value compared to traditional lectures and seminars of the (a) eLearning module, (b) individual workstation-based case-work, (c) supervisor mediated small-group case discussion and (d) the concise lecture for learning success. e Overall rating (0—worst to 100—best) of medical students receiving the new case- and competency-based format compared to the rating of students that had received traditional lectures and seminars prior to the transformation of the teaching format. **p < 0.01

Perceived fun during the new case- and competency-based course

Third, we analyzed the students’ perceived enjoyment while learning abdominal radiology in a case- and competency-based format as implemented in this study since it has been shown that enjoyment is associated with deep learning improving maintenance of the educated content [17]. Here, students agreed that the description and analysis of findings in radiological imaging data was interesting (6.9 ± 2.0, Fig. 4a) and made fun (6.6 ± 2.1, Fig. 4b). Additionally, students strongly agreed (8.9 ± 1.5, Fig. 4c) that the new case- and competency-based format was more fun than a traditional radiology lecture or seminar.

The interest to pursue a career in radiology

Fourth, we evaluated if the case- and competency-based course changed the career plans of medical students regarding their future specialization (Supplementary Fig. 1a–c). Here, medical students agreed that an internship in a radiology department during medical studies would be of interest (6.0 ± 2.9), while this agreement was slightly lower after the course (5.6 ± 2.9, p = 0.002, Cohen’s d = 0.23 95% CI [0.09–0.37]). However, after the course, students had unchanged disagreement with the interest to absolve a part of the last practical year of medical studies in radiology (3.9 ± 2.7) or to pursue a residency in radiology (3.2 ± 3.3) as compared with before the course (4.0 ± 2.6, p > 0.05, d = 0.16 95% CI [0.01–0.30], or 3.2 ± 2.4, p > 0.05, d = 0.08 95% CI [0.06–0.22], respectively).

Thus, despite a slight decrease in students’ interest in pursuing an internship in radiology during their studies (p = 0.002, Cohen’s d = 0.23), which indicates a small effect, the new course had no significant impact on their interest in completing part of their final practical year or pursuing a residency in radiology.

The pedagogical style of the new case- and competency-based course

Fifth, we analyzed students’ perception of the chosen format for the new case- and competency-based radiology course. Here, students agreed (6.6 ± 2.0, Fig. 5a) that the eLearning module of the first part helped to learn about abdominal imaging in a clinical context. Further, the students strongly agreed (8.8 ± 1.6, Fig. 5b) that the independent case work (scrolling, marking in imaging datasets, etc.) has more supported learning about abdominal radiology than a traditional lecture or seminar. However, besides the first self-study phase, the students strongly agreed (8.5 ± 2.0, Fig. 5c) that the second supervisor-accompanied small group discussion phase was an important complement to ensure learning success and solve open-ended questions. Interestingly, next to the modern design of the first- and second case- and competency-based phase, the students still agreed (7.5 ± 2.1, Fig. 5d) that the concise summarizing lectures were a valuable addition for the overall learning success.

Furthermore, we compared the mandatory overall evaluation of medical students that absolved the new case- and competency-based course with the control group of medical students that had previously received the same teaching content via traditional lectures and seminars. Here, students’ rating of the new case- and competency-based format (80.2 ± 1.7) was significantly better than the rating of traditional lectures and seminars (66.2 ± 1.9, p = 0.01, Fig. 5d).

Last, we also analyzed the evaluations’ free-text comments on the new case- and competency-based course. In total, the 235 students formulated 152 free-text comments (free-text response rate of 64.7%), which may have contained positive or negative feedback or both. The most frequent comment for improvement was, that the educational day was too long for a significant part of students to keep up the concentration for effective learning (n = 70 comments, 46.1% of comments, 29.7% of students). Further, comments suggested that slide handouts of the short lectures (n = 24, 15.8% or 10.2%, respectively) be provided, which had already been implemented after the first course and therefore resulted in no further comments in this regard. Additionally, students requested direct software feedback with the correct/incorrect answers, in addition to the discussion with the supervisor (n = 24, 15.8% or 10.2%, respectively). Next to other minor comments not related to the concept of the course (n = 9, 5.9% or 3.8%, respectively), some students (n = 12, 7.9% or 5.1%, respectively) complained about the loud acoustics in the course room, especially during the group discussion phase. Positive free-text feedback mainly included the overall concept (n = 48, 31.6% or 20.0%, respectively), motivation and pedagogical skills of the supervisors (n = 19, 12.5% or 8.1%, respectively), and the time schedule (n = 7, 4.6% or 3.0%, respectively). Further, an impressive majority (99.5%) of medical students voted to continue the newly implemented case- and competency-based course in the future.