The Effectiveness of Problem-Based Learning in Improving Critical Thinking and Problem-Solving Skills in Medical Students: A Systematic Review of Fifteen Years’ Experience (2005-2019)

Background: An ongoing challenge for medical education in the twenty-first century is determining the best method to foster problem-solving and critical thinking in learners. These higher-order aptitudes help to prepare medical doctors for practice in a rapidly evolving health system. In medical education, Problem-Based Learning (PBL) is an instructional pedagogy in which pupils are challenged to seek answers to authentic patient scenarios in small groups. PBL techniques are proposed as one method to enhance pupils’ learning abilities including critical thinking and problem-solving. Aim: This systematic review was conducted to search for evidence from the past fifteen years of literature, demonstrating the capability of PBL to improve critical thinking and problem-solving skills for medical students. Review Question: Is there evidence to support the capability of PBL to improve problem solving and critical thinking skills in medical students? Methods: The search process was conducted through electronic databases on publications related to the impact of PBL, particularly, on two fundamental skills; critical thinking and problem-solving for medical students. The search process was restricted to publicationsbetween January 1, 2005 and December 31, 2019. Four electronic databases were searched, namely; Medline, PubMed, EMBASE and Scopus. The Best Evidence Medical Education (BEME) guidelines were utilised to guide the way this systematic review was conducted. Quality assessment was performed through rating the evaluation methods of the included studies. This rating was through employing a five-point Likert scale (1= strongly disagree to 5= strongly agree) for each study in relation to three items; the appropriateness of study design, the implementation of the study as well as the appropriateness of data analysis. The rating for each study was then mapped to a grade from grade 1 (low) to grade 5 (high), which aligns with the BEME strength of the study findings. Results: Searching the four aforementioned databases produced 657 publications, including 249 duplicates. Therefore, 408 publications were screened based on their titles against inclusion and exclusion criteria, leaving 86 articles to screen their abstracts. A further 9 articles were manually obtained such that a total of 95 articles were obtained for a review of their abstracts. Forty-one met the criteria for full text review. Following the full text review, twenty-nine articles were excluded. Therefore, twelve studies were included in this systematic review. The BEME strength of study findings were as follows; only two of the reviewed studies were graded as grade 5, four were graded as grade 4, and six were graded as grade 3. Of the twelve studies reviewed, only five studies provided evidence in support of the capability of PBL to improve critical thinking and problem-solving skills among medical students. Two of these five studies were graded as grade 5 and two were graded as grade 4, while one was graded as grade 3. Discussion: The available evidence in this systematic review provided limited support of the claim that PBL improves medical students’ critical thinking and problem-solving aptitudes. Only five studies provided evidence in support of this claim, while the remaining seven studies did not. Two of these seven studies assessed only the knowledge, comprehension, and application domains, as their evaluation of problem-solving and critical thinking abilities was based on student perspectives. A further two of these seven studies, where the description provided either for case-analysis tests or modified essay questions, did not give an actual indication for measuring critical thinking and problem-solving skills. Another two of these seven studies did not describe their written tests i.e. case-analysis tests and proxy questions that are purported to measure higher-order skills, including critical thinking and problem-solving. This prevented the use of the findings from these two studies as evidence to support the specified review question. The remaining study reported that PBL students’ scores in the final assessment did not improve significantly (p>0.05) compared to the initial assessment. Conclusion: There is very little published evidence over the last fifteen years supporting the claim that PBL improves critical thinking and problem-solving skills in medical students. Therefore, recent practice is not based on evidence. As such, investigations are required to legitimise the claims that PBL improves critical thinking and problem-solving skills for medical students. Key words: Problem-Based Learning, Critical Thinking and Problem-Solving Skills, Medical Students