Due to demographic and disease pattern changes along with patient’s needs and aspirations, healthcare professionals are required to develop new skills such as creativity (1), leadership, teamwork, empathy, and communication skills (2), in order to provide high-quality, safe, and effective patient care (3). Physicians must be prepared to deal with all types of environments and make decisions in situations of crisis and epidemics (4). Therefore, skills for managing people-centered care, managing complex tasks, and creating a positive work culture are needed (5). Being aware of the importance of the development of a set of skills beyond knowledge acquisition in 2017, the United Nations Education, Scientific and Cultural Organization (6) suggested the development of critical thinking (CT) as a learning outcome, which is defined as “the ability to question norms, practices, and opinions; to reflect on own[sic] one’s values, perceptions, and actions and to take a position in the sustainability discourse” (7). In fact, CT seems to be a key ingredient for commitment to lifelong learning (8) and a deep learning experience, allowing a better understanding and ability to deal with complex concepts and problems (9). It has been positively related to academic achievements (10) and better patients’ assessments, diagnoses, and care in the future (11). Critical thinkers seem to develop a more questioning mind, better critical appraisal abilities, and a positive attitude concerning evidence-based medicine (12). Thus, fostering students to develop CT has been a universal goal “to create better doctors” (13), a desirable outcome that should be developed in an early stage of their training, as skills develop through experience and practice (11, 14).

According to the American Philosophical Association, critical thinking encompasses a broad set of cognitive skills such as interpretation, analysis, evaluation, inference, explanation, self-regulation, and dispositions, including truth-seeking, open-mindedness, analyticity, systematicity, self-confidence, inquisitiveness, and maturity (15). Definitions of CT in medical education tend to emphasize logical or rational thinking—the ability to reason, analyze information, evaluate alternatives, assess arguments and evidence, and reach relevant and appropriate solutions to a problem (16). Moreover, in medicine, CT has also been described and identified nearly as synonymous with “clinical judgment” (CJ), “clinical reasoning” (CR), “diagnostic thinking,” “problem-solving,” or “type 2 thinking” terms involving a mental process used to think through problems and achieve a final decision (11).

Although CT can be taught, both pedagogical and assessment practices are challenging, and there is no consensus on the most effective teaching approach. In part, the instructional methods are challenging due to the different understanding of CT. For instance, Krupat et al. (17) found that 43% of doctors describe CT as a process, 41% as a skill or ability, and 16% as disposition. Therefore, teaching CT remains both a challenge and a necessity in medical education (9).

Our systematic review aims to investigate the effectiveness of the pedagogical practices that are currently used to foster the development of CT/CR/CJ skills and/or dispositions in undergraduate medical students. The specific objectives of this review are as follows: (1) to identify the pedagogical practices currently in use to promote the development of CT/CR/CJ skills and/or dispositions in undergraduate medical students; (2) to identify the tools that are being used to assess CT/CR/CJ skills and/or dispositions in the above conditions; and (3) to investigate the effectiveness of those pedagogical practices, considering the CT/CR/CJ skills and/or dispositions gains, the assessment tools, and the intervention context.

This study followed the Cochrane recommendations (18–22) and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Guidelines (23) (Supplementary material—PRISMA Checklist). The protocol for this systematic review is registered on Open Science Framework (OSF): doi: 10.17605/OSF.IO/8PJ26.

Although this systematic review was based on the approach used in a previous study (24), it explored the effectiveness of pedagogical practices used to foster CT/CR/CJ skills and dispositions exclusively in undergraduate medical students while also including other pedagogical outcomes.

Due to differences in study designs and methodologies, as well as the diversity of CT/CR/CJ pedagogical practices and respective assessment tools used in the selected studies, it is challenging to identify the most effective pedagogical practices in fostering the development of CT/CR/CJ skills and/or dispositions in medical students.

Nevertheless, pedagogical practices, such as cognitive/visual representation, simulation, literature exposure, test-enhancing and team-based learning, clinical case discussion, error-based learning, game-based learning, explicit CT instructions, and the innovative curriculum approaches, seem to be effective in the development of the CT/CR/CT skills and/or dispositions as most of them reported CT/CR/CJ general gains (++). Alternatively, pedagogical practices, such as debate, journal club, reflective writing, dialog narrative approach, and case creation, seem to have a positive impact on students’ learning experience, showing improvements in student’s knowledge, satisfaction, and perception of the development of CT/CR/CJ. However, these outcomes do not directly express CT/CR/CJ since, knowledge per se is not enough for its development (60). In addition, the concept of CT/CR/CJ is still complex and ambiguous, leading to different perceptions among students, teachers, and experts on CT (17). Therefore, no conclusion can be inferred either from knowledge improvements or students’ perceptions of the development of CT/CR/CJ and the effective development of those skills.

When comparing CT and CR pedagogical practices, despite the differences in the medical curriculum length across countries, usually the first years are basic science-oriented while the last years are clinical training-orientated. This may be particularly interesting given that CT pedagogical practices seem to be mainly employed during the first 2 years of the curriculum, and CR pedagogical approaches are more commonly used in the last years, which may be related to the fact that CR constitutes CT application within a clinical context (61).

Most studies seem to foster CT mainly through the development of skills and dispositions. On the other hand, studies fostering CR development, in line with past evidence, were more profession-oriented and focused mainly on the development of diagnostic and decision-making skills (24, 62). In addition, the studies evaluating the effectiveness of pedagogical practices were mainly focused on fostering and assessing both CT and CR skills, whereas studies focused on dispositions were limited (n = 3) and only used in the context of CT (31, 32). Therefore, this can be related to how doctors conceptualize CT (i.e., in their definitions) (17). As we know, CT “requires mastery of context-specific knowledge to evaluate specific beliefs, claims, and actions” (63). Therefore, it may be useful to apply pedagogical practices that encourage the development of CT dispositions as “open-mindedness, willingness to reconsider, honesty about personal biases and persistence” (15) in the early years of the medical curriculum. As students acquire a deeper knowledge, pedagogical practices that foster CT/CR skills, more oriented to clinical decision and problem solving, could be explored. According to students’ needs and learning objectives, CT and CR pedagogical practices could be combined to achieve a more comprehensive development of skills and dispositions.

Regarding the “curricular” and “extracurricular” approaches, we have found contrasting results, with both reporting CT/CR/CJ general gains (++) (56.3% versus 58.8%) and CT/CR/CJ no gains (−−) (6.3% versus 17.6%). In agreement with previous literature, some authors believe that CT skills can be assessed regardless of the context, while others disagree (64).

Regarding the subject specificity, most studies that adopted an “immersive” followed by an “infusive” approach positively impacted the development of CT/CR/CJ skills and/or dispositions and students’ learning experiences (92.0 and 85.7%, respectively). Considering these results, and that the only study with a mixed approach reported CT/CR/CJ no gains (−−), it seems that an approach in which students are encouraged to think critically about a subject (subject-related) could be more effective, especially when they have prior knowledge on the topic. In fact, some studies show the need for a sustained specific-knowledge background to enable its application in more complex systems (60, 65). In contrast, when comparing the “immersive” and “infusive” approaches, despite the limited number of studies reporting an “infusive” approach (n = 7), we can suggest that the most effective are those that make these principles explicit to students. Furthermore, gains resulting from the explicit CT instructions approach corroborate this (38). Therefore, it would be interesting to incorporate CT as a specific subject in the medical curriculum, ideally during the first year.

Regarding the intervention length, some studies report that longer, progressive, and continuous interventions can lead to better outcomes, indicating that length may be an important factor in the development of CT. Although supported by a previous systematic review (24), the results herein presented are not enough to support this association.

Regarding the regime of the approach, most strategies applied the face-to-face approach, although both face-to-face and e-learning methodologies seem to positively impact the development of CT/CR/CJ.

Both individual and collaborative approaches seem to have a positive impact on the development of CT/CR. However, the learning experience can be improved by students’ engagement in discussions with each other (56). In addition, pedagogical practices seem to increase their efficacy in the following order: passive < active < constructive < interactive learning environments (66). This highlights the need to better understand the role of group interaction in the development of CT when assessing the impact of the number of students per group, both large (7 to 8 medical students) and small groups (2 medical students), and induced CT/CR/CJ general gains (++). In addition to group size, constitution seems to play a pivotal role in the effectiveness of the pedagogical practices. For instance, in heterogeneous groups, the strongest students may end up doing all the work, especially when a limited amount of time is available to perform a task. However, heterogeneity may also breed different backgrounds and perspectives on a subject, thus enriching discussion and aiding group productivity (67). In contrast, a homogeneous group will probably operate on the extremes, with the strongest groups completing their work more quickly, while the weaker groups need more time or do not complete the task by themselves (67).

Additionally, the pedagogical practice effectiveness seems to depend on the tutor and his CT proficiency (44, 68, 69). Although most studies mentioned instructional support (87.9%) or feedback (66.7%), only a minority considered their educational role and impact in fostering CT. Kim (31) highlights that activities based on interactions and feedback (e.g., group discussion and narrative comments) were more advantageous for CT development than those done individually (i.e., book reading and essay writing) (31). In agreement, some authors (28, 46, 70) suggest that the presence of an instructor through students’ guidance and prevention of misunderstandings or misconceptions can benefit both the pedagogical approach and learning experiences. Instructional support and feedback ensure that learners with learning difficulties are adequately supported in their learning process (47).

The lack of results regarding the learning outcomes may be related to differences between studies in terms of methodology and design, particularly in the intervention length, subject specificity, and assessment tools. Hence, negative outcomes might have resulted from the unfamiliarity with the approach that may have led to less proficiency (37) or from the short duration of studies with high cognitive load interventions that may compromise student adjustment to pedagogical practice and consequent performance (48).

Overall, developing CT/CR/CJ skills represents a complex learning challenge. The learner is involved in a combination of meaningful learning activities that promote both knowledge, by integrating new information into pre-existing frameworks (71), and skills such as observation, analysis, evaluation, contextualization, questioning, and, finally, reflection on a subject or a problem (72, 73). A learning environment that promotes individual growth through peer instruction, meaningful learning, and learning by doing, in which students play an active role in the learning process and receive proper feedback, is essential to ensure the efficacy of a pedagogical approach (49).

To the best of our knowledge, this is the first systematic review focused on the effectiveness of CT/CR/CJ pedagogical practices in medical education. Some limitations were identified. Although most studies were mainly focused on pedagogical practice, the presence of other approaches may have had an impact on the results. In addition, gains may also have been influenced by the educational environment, other concurrent courses, or the existence of residual or unmeasured confounders (31). Caution must also be taken with the studies describing assessment tools not previously validated for the study population (e.g., general standardized tests), as well as when a domain-specific non-standardized test or rubric was used, compromising the reproducibility of the intervention in other fields, as well as when studies relied upon a post-test assessment and/or there was no control group or other comparative intervention. Finally, no language restrictions were applied to our research strategy, but the search terms we used were in English. Given that most of the non-English language journals translate the abstract into English, we suggest that the search terms used only in English did not significantly affect the search outcomes.

Pedagogical practices that actively engage undergraduate medical students in the learning process are likely more effective than traditional lectures in fostering the development of CT/CR/CJ skills and/or dispositions. However, comparison between practices is not easy due to the limited number of studies and diverse methodologies and assessment tools employed. Despite these challenges, our systematic review raises important questions about the timing, length, curricular context, regime (face-to-face vs. e-learning), and format (individual vs. collaborative) of interventions that should be carefully considered to enhance the effectiveness of the pedagogical approaches. Furthermore, it acknowledges the complexity of fostering critical thinking in medical education, recognizing that there is no “one-size-fits-all solution.” Overall, we can conclude that different pedagogical practices should be used and combined throughout the curriculum considering diverse learning environments and student needs to effectively enhance CT skills and dispositions of medical students.

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

BA: Conceptualization, Investigation, Methodology, Writing – original draft. SG: Investigation, Methodology, Writing – review & editing. LR: Conceptualization, Supervision, Writing – review & editing, Investigation, Methodology.