Using Nobel Prize case-based learning in Medical Immunology to cultivate critical thinking dispositions for medical undergraduates | BMC Medical Education

Research participants and design

We used a quantitative descriptive pretest-posttest control group design to assess the impact of Nobel Prize-inspired pedagogical reforms on the critical thinking dispositions of medical students (Fig. 1). Due to the lack of research on cultivating critical thinking in Medical Immunology, we calculated the sample size by referring to a published study [16]. In that study [16], the average score of critical thinking in the experimental group was 9.47 ± 2.669, while that in the control was 11.00 ± 2.591. We set the significance level at α = 0.05 and the 90% confidence level at 1-β = 0.9. According to the formula n= (Z_α+Z_β)²×σ²/δ² for the pretest-posttest study design [17], with Z_α=1.96, Z_β=1.28, σ = 2.669, and δ = 11.00-9.47 = 1.53, we estimated the required sample size for each group to be approximately 32 cases. Considering a potential dropout rate of 10%, we finally determined the total number of cases in each group to be 35. Therefore, a convenience sample of 70 medical students from 4 classes in BUCM, China, were invited to take part in the study. Over the course of a semester, two of these classes, totaling 35 students, served as the control group to receive conventional teaching methods. The remaining two classes, also numbering 35 students, formed the experimental group that underwent critical thinking-based instruction. The inclusion criteria included having registered for the Medical Immunology curriculum and being a second-year undergraduate medical student. The exclusion criteria were defined as studying a non-medical major, not being a sophomore, expressing reluctance to participate, and involvement in other case-based educational reforms.

Flow chart of the teaching process of Medical Immunology for two groups

Teaching methods

Both the experimental group and control group were instructed by the same experienced lecturers with the same syllabus and class hours, which mainly included theoretical learning and practical operation. We outlined the methods taken to ensure that participants were blind to the group allocations, thereby reducing the potential for bias in the learning process.

The control group

This method is regarded as a traditional educational approach, which emphasizes that the lecturer proactively transmits theoretical knowledge and the students passively receive knowledge. Students received a three-step teaching method consisting of self-study before class, followed by in-class or laboratory lectures, and concluded with post-class quizzes or assignments. Each step was executed with strict adherence to the textbook, curriculum, and the established teaching schedule, with a lack of access to our Nobel Prize material library.

The experimental group

This method was grounded in traditional knowledge teaching, further incorporating our characteristic Nobel Prize material library, and implemented as a case-centered approach to fully developing students’ critical thinking. Our teaching process implementation mainly included pre-class learning, classroom introduction, group discussion, experimental teaching, and post-class assessment. We informed this approach by the integration of Nobel Prize cases throughout the curriculum, as illustrated in Fig. 1.

“Antitoxin and immunoserum therapy” (Emil Adolf von Behring, 1901) is a classical Nobel Prize case in the chapter on “Antibody”, which represents a fundamental topic of immunology basis as well as a critical area for guiding the defense against pathogenic infections. Therefore, given this connecting link between the preceding and the following in the curriculum, this paper adopted “Antitoxin and immunoserum therapy” as a classical example to elaborate the design and implementation of a critical thinking-based teaching methodology.

Step 1: Pre-class learning assignments containing the narratives of Nobel Prize-winning immunologists via an online digital platform

Firstly, we produced personalized classroom teaching slides incorporating the scientific narrative and the Nobel-winning legacy of Emil Adolf von Behring, who won the Nobel Prize for his pioneering work on “Antitoxin and immunoserum therapy”. One week before the scheduled class, students received a pre-class learning task list about “Antibody” and slides on “Antitoxin and immunoserum therapy” through the online digital platform “Rain Classroom”. We expected students to engage with the self-study materials and complete a corresponding self-assessment quiz by the night before class. The approach ensured that students had a foundational understanding of the history behind the discovery of antitoxin and the development of animal serum therapy, preparing them for the ensuing online class discussions. Relying on the quick and convenient statistical function of these intelligent classroom platforms, we could adjust the online class content, check leakage, and fill a vacancy in class according to the student’s completion and participation of self-test questions.

Besides, five minutes before class, we broadcasted documentaries or interesting videos to review the arduous research journey of Behring and encouraged students to hold the values of truth-seeking, critical questioning, innovation, objective realism, and perseverance which are essential traits in the scientific endeavor.

Step 2: Construction and application of paper and electronic textbook resources containing Nobel Prize-related materials for classroom teaching

In class, we selected “Medical Immunology and Pathogen Biology”, a national planning textbook published by Science Press [18], as the textbook for this course. Three famous teachers of Chinese medicine universities compiled this textbook for the extensive use of medical majors and other medical majors. Our course team developed an array of dynamic digital learning resources to enrich the most recent edition of this textbook. These resources included illustrative diagrams and engaging animations that corresponded to the course contents, offering students a more interactive and visually stimulating learning experience. As well, students could also access diversified slides incorporating immunological scientist materials and mind maps through QR codes, which aimed to improve their learning interest, enhance their intellectual curiosity, and open their scientific thinking.

Step 3: Implementing a series of class seminars on classical Nobel Prize-related materials for classroom teaching

To foster academic engagement among our students, we implemented a series of class seminars on “Antitoxin and immunoserum therapy”, to inspire a deep dive into Behring’s significant contributions from his discovery and experimentation of Corynebacterium diphtheriae to his groundbreaking work in the field of Immunology. By selecting different stages of Behring’s story, we motivated students to delve into topics such as pathogenic bacteria, disinfection, and sterilization techniques. This way encouraged students to embody the spirit of hard work, persistence, continuous innovation, and the courage to make mistakes. Furthermore, through highlighting the collaborative efforts of Behring, Shisaburo Kitasato, and other bacteriologists in developing antitoxin and immunoserum therapies, we cultivated an appreciation for integrating multi-team research findings and scientific cooperative spirit. During this process, the introduction of the diphtheria vaccine serves as a springboard for students to actively explore the immunological mechanisms behind antitoxins and vaccines.

Step 4: Introducing the flipped classroom mode for small group discussions on classical Nobel Prize-related materials

In addition to traditional classroom settings, we utilized the flipped classroom model, allowing students to present the scientific literature published by Behring in small group discussions. We also encouraged them to explore the corresponding scientific papers involved in Behring’s Nobel Prize, such as “Disinfection in the living body” [19], “Emil Behring’s medical culture: from disinfection to serotherapy” [20], and “Emil von Behring: translational medicine at the dawn of immunology” [21].

Step 5: Recording classical experimental video resources related to the Nobel Prize for extra-curricular learning

To further enrich their learning experience, our teaching team recorded an operation video demonstrating the preparation of immune serum for students’ extracurricular learning, to enhance their awareness of immune serum therapy and improve their practical skills during laboratory sessions. Through these diverse methods, we not only aim to impart knowledge but also to inspire students to draw lessons from Behring’s journey. His narrative of ascending from humble origins to becoming a highly proficient and accomplished researcher stands as a testament to the value of diligence and perseverance.

Step 6: Multi-level assessment and long-term tracking of Nobel Prize-based teaching effectiveness

After a week of instruction, the teacher implemented questionnaire surveys to assess the teaching effectiveness among the students in the class. The students uniformly expressed high satisfaction with the quality of the class, stating that this teaching mode made the knowledge points clearer, enhanced learning efficiency, and sparked greater interest in learning. Finally, we included the pertinent case study questions in the final examination of both groups to evaluate students’ analytical and critical thinking dispositions, thus reflecting the impact of Noble Prize-based classroom reforms combined with the usual performance. As well, we encouraged open academic discussions as an extension of learning beyond the classroom, fostering a valuable exchange between teachers and students that would persist throughout the semester and even after graduation.

Assessment instruments

California Critical Thinking Dispositions Inventory (CCTDI), a standardized commercially prepared tool based on robust theory and one of the most widely used to measure critical thinking disposition, was further revised to CTDI-CV according to the local characteristics in China by Peng et al. [14]. Therefore, this study applied CTDI-CV to assess the critical thinking dispositions of the included Chinese subjects. The content validity of CTDI-CV is 0.89, the α value is 0.90, and the internal consistency of each dimension is between 0.54 and 0.77. The same validity and reliability values have been validated in two large cohorts of medical students from different medical institutions in China [8, 15], which confirmed the suitability as a measurement tool for medical students’ critical thinking disposition within the context of this study. CTDI-CV contains 7 subscales that are truth-seeking, open-mindedness, analyticity, systematicity, confidence in reasoning, inquisitiveness, and maturity in judgment. Each dimension consists of 10 questions, for a total of 70 questions, with 6 choices after each question.

This research used a Likert six-point scale to score positive and reverse questions [1]. There were six grades for positive questions: strongly agree, quite agree, somewhat agree, generally agree, quite disagree, and strongly disagree, corresponding to 1 to 6 points, respectively. In contrast, reverse questions corresponded to 6 to 1 points, respectively. A total score ≤ 210 indicates a negative overall critical thinking disposition, a total score of 211 to 279 signifies an ambivalent disposition, a total score ≥ 280 refers to a positive disposition, and a total score ≥ 350 means a strongly positive disposition. As for the critical thinking disposition in a single dimension, a score ≤ 30 represents negative, a score of 31 to 39 means ambivalent, a score ≥ 40 suggests positive, and a score ≥ 50 refers to strongly positive.

Questionnaire distribution and data collection

All students in the control and experimental groups received CTDI-CV before and after the semester. The course instructors provided clear instructions on how to properly undertake the test and elucidated the purpose and nature of this questionnaire. Through the entire process of filling out the questionnaire, we mandated each student to complete it independently without any form of consultation or discussion with their peers to ensure the integrity of the individual responses.

Data analysis

We used the GraphPad Prism 9.0 software to perform statistical analysis of the variance and difference of the measured data, as well as generate the visualized charts showing statistical differences. Before proceeding with the comparison between and within groups, we performed the Normality and Lognormality Tests via GraphPad Prism 9.0 software. The resulting p values all exceeded 0.05, suggesting that the data conformed to a normal distribution. Therefore, we subsequently conducted unpaired t-tests to determine statistical significance in the scores of CTDI-CV between control and experimental groups, as well as assigned paired t-tests to determine statistical significance between pre-test and post-test in the experimental group. Pearson correlation analysis acted as an approach to exploring the correlation between the total scores of CTDI-CV and the final grades. p values below 0.05 indicated a significant difference. We presented data as mean ± standard error of the mean (mean ± SEM).