Learning Effectiveness and Satisfaction of International Medical Students: Introducing a Hybrid-PBL Curriculum in Biochemistry

A biochemistry course is a fundamental but important subject in medical education in China. In recent years, the number of international medical students has increased. Curriculum reform in biochemistry teaching is needed because of the knowledge limitations of students, a close linkage of biochemical content with clinics, the shortcomings of lecture‐centered teaching, and the requirements for early clinical practice training and competence. In this study, we analyzed a novel curriculum reform, “Hybrid–PBL,” which combined problem‐based learning (PBL) with biochemistry lectures and was implemented for biochemical teaching at Dalian Medical University (DMU) in China. The change in curriculum affected 189 international medical students. This study selected two PBL cases concerning the basic biochemical issues of carbohydrate metabolism and liver biochemistry for the analysis, and ten examples of learning issues for each case were reported by the international students. A questionnaire was utilized to evaluate students’ perceptions of the Hybrid–PBL, and examination scores were analyzed to assess the curriculum reform in biochemistry teaching. A statistical analysis revealed that the Hybrid–PBL curriculum was well accepted by the international students as an effective supplement to lecture‐centered teaching programs. The students obtained more abilities, higher examination scores, and an improved understanding of biomedical information from the Hybrid–PBL program than from conventional teaching methods. Our study was an innovative trial that applied a PBL curriculum to the specific discipline of biochemistry and may provide a potential and promising new teaching method that can be widely utilized. © 2017 by The International Union of Biochemistry and Molecular Biology, 45(4):336–342, 2017.

Problem‐based learning; biochemistry; medical education; international medical students

The Bachelor of Medicine/Bachelor of Surgery (MBBS) and the Bachelor of Dental Surgery (BDS) programs have strongly attracted international students to study medicine in China because of the unique advantage of these medical education programs. Dalian Medical University (DMU) of China is one of the major universities that is authorized to enroll international medical students in its MBBS and BDS programs. DMU has been praised for its excellent quality of international undergraduate teaching by the Ministry of Education in China. Currently, more than 1,300 international medical students from more than 70 countries study at DMU.

It is important for medical students to be trained in clinical competence, which refers to physicians’ capability to perform their activities in a healthcare setting while they define and manage their patients’ health problems and acquire the skills that are needed to solve clinical problems [1] . However, evidence suggests that a doctor's clinical competence is poor under the conventional educational program of lecture‐based learning [1] , [2] , [3] , and crucial changes in teaching modules have occurred in medical education since the last quarter of the 20th century in many countries [4] , [5] , [6] , [7] , [8] . These changes have often been characterized by student‐centered learning that is called problem‐based learning (PBL). PBL originated in medical education at the McMaster University Medical School in Canada in 1969 and is a student‐centered pedagogy in which students work in small groups to study practical medical cases and solve real‐world problems [6] , [9] , [10] . PBL is considered to be a learning technique with great potential to improve medical practice. Numerous medical universities worldwide have applied a PBL curriculum as a mainstream teaching pedagogy.

Biochemistry refers to the description of illness in molecular terms and contributes to understanding the role of molecular mechanisms and genetic information in health and disease [11] , [12] . Although medical biochemistry has a fundamental role in specialized clinical applications, most medical students in China attach little importance to the study of biochemistry. Medical Biochemistry is known to be a complicated basic science in which students may have significant difficulties in understanding and comprehension [13] . Biochemistry is an independent biomedical science course that is generally taken during the early years of the degree and is required for all medical students at DMU. Therefore, curriculum reform remains a pressing issue to actively motivate students to study biochemistry. Rather than simply teaching the current advanced biochemical knowledge and phenomena, medical education should embrace an integrative problem‐based teaching style, particularly for molecular medicine. This new method of teaching will equip doctors and other healthcare professionals with the knowledge that is required for a lifetime practice of molecular medicine.

In this study, according to the Chinese education module and the faculty at DMU, we reformed the curriculum in biochemistry teaching by introducing a Hybrid–PBL program that combined a PBL curriculum with conventional lectures. The curriculum trial explored the feasibility of adopting PBL as a supplement to the medical biochemistry curriculum and encouraged students to study biochemistry with interest and enthusiasm.

International medical students at DMU in the second semester of their first academic year were selected for this study. Three cohorts of students who were admitted to DMU in the spring of 2013 (2013 Spring), the autumn of 2013 (2013 Fall), and the spring of 2014 (2014 Spring) were included in this study. The PBL group included two cohorts of students (2013 Spring and 2013 Fall). Eight to nine students were grouped with a chairperson to organize case discussions, and the discussions were recorded for a detailed analysis. The non‐PBL group included the 2014 Spring cohort. The facilitators were responsible for the biochemistry lectures and instructing the PBL class. The PBL class was conducted in a large classroom facility. The ethics of this study has been approved by the IRB (Institutional Review Board) of Dalian Medical University.

Two PBL cases (Table [NaN] ) regarding basic biological issues were introduced after their relevant lectures were completed. Case 1 featured carbohydrate metabolism and lipid metabolism. Case 2 featured liver biochemistry. These cases were designed by the facilitators to help the students to better understand biochemistry. Each PBL class was 2 h long, and each case required 4 h per week. The cases were designed for two sessions. During the first PBL session, the students were required to identify facts, develop hypotheses, and generate a set of learning issues that were assigned to each student. All students were required to submit a written report on the assigned learning issue to the facilitator by e‐mail prior to the beginning of the second session. The students were allowed to access online resources to overcome their difficulties in understanding certain points. During the second session, the chairperson of each group represented their group members and presented their learning issues, which had been summarized by all the group members and reviewed by the facilitator. At the conclusion of the PBL class, the facilitator summarized the key learning objectives and the relevant biochemical knowledge that were included in the cases.

General descriptions of the two PBL cases introduced in the Hybrid–PBL curriculum

1 Representative examples of learning issues presented by international medical students.

After completion of the biochemistry lectures, the international medical students were asked to complete a questionnaire to identify the effectiveness of this new teaching method and to analyze the Students’ attitudes on and satisfaction with the Hybrid–PBL program. A cross‐sectional survey was conducted among the international medical students. The students voluntarily participated in the survey and were assured of the anonymous nature of their responses. The questionnaire was designed by the facilitators.

At the end of the semester, the students were required to take a written biochemistry examination. In this study, the examination questions included three parts: Multiple Choice (60 scores), Terminology (20 scores), and Essay Questions (20 scores). Statistical analyses of the examination scores were conducted, and the non‐PBL and PBL groups were compared using different questions with a similar difficulty and identical questions. In addition, the scores of the non‐PBL groups were analyzed using different questions that were obtained from previous test records.

The data were statistically analyzed by the SPSS software for Windows, version 16.0, and Microsoft Office Excel 2007. The values were presented as number counts (with corresponding frequencies or percentages), and the means ± the standard deviation (SDs) were calculated for the continuous variables. For the between‐group comparisons, we used two sample t tests for the continuous variables and Pearson chi‐square tests for the categorical data. A p value of <0.05 was considered to be statistically significant in this analysis.

In the PBL class, the grouped students actively worked together to review the relevant biochemical knowledge and studied the patient's basic information in addition to the laboratory data. The students developed their learning needs and made preliminary judgments regarding the diseases that were discussed. Then, each student submitted a detailed written report to demonstrate their biochemical knowledge concerning the issue that was assigned in the first section (Table [NaN] ). In the second section, the chairpersons demonstrated the knowledge that they gained from their learning issues by delivering a presentation in class. Accordingly, broad and multiple learning issues encouraged the international medical students to learn more from the PBL class than from the classes that only included conventional lectures. The PBL class allowed the international medical students to consolidate the knowledge that they learned from the lectures and broadened their views and knowledge.

A cross‐sectional questionnaire analysis was conducted among the international medical students, and a cover letter that addressed the objectives of the project was approved by DMU. In addition, a notice regarding confidentiality issues was distributed with the questionnaire. The questionnaire data were collected over a period of 1 year.

A cross‐sectional sample of 180 international medical students in the PBL group and 93 in the non‐PBL group returned completed questionnaires. The response rate was 95.2 percent of the target (180/189) for the PBL group and 92.1 percent (93/101) for the non‐PBL group. Table [NaN] presents the characteristics for the participants of this study. For the 189 participants of the PBL group, 88 (10 dental students and 78 clinical students) were from the 2013 Spring cohort, and 101 (25 dental students and 76 clinical students) were from the 2013 Fall cohort. The majority of students came from Thailand (31.7%), South Africa (12.7%), and Zambia (10.0%). For the 101 participants of the non‐PBL group, 30 were dental students, and 71 were clinical students. The majority of students came from Thailand (17.8%), The Kingdom of Bahrain (11.9%), and India (9.9%). Most of the participants (68.2%) were high school graduates, and the remainder (31.8%) had earned a bachelor's degree. The present prospective cohort study was conducted by two members of the biochemistry faculty who implemented the Hybrid–PBL teaching program.

Analysis of the capabilities obtained by the PBL group in the Hybrid–PBL curriculum

Ten items (which are presented in Table [NaN] ) regarding the abilities that were obtained from the Hybrid–PBL program were assessed in the questionnaire. The responses to the questionnaire items were described by reporting the percentage and numbers of students who selected various options. A questionnaire analysis revealed that the majority of students agreed that the PBL module was helpful to them to develop self‐directed learning skills (88.1%), group collaboration skills (83.3%), public speaking skills (81%), skills in writing reports and articles (81%), the ability to work independently (71.4%), presentation skills (66.7%), interpersonal skills (61.9%), the use of information resources (61.9%), and the ability to work well under stress (57.1%). Most of the international medical students believed that they had obtained more abilities from the Hybrid–PBL curriculum than from the conventional learning methods.

Table [NaN] displays seven items regarding the application of the PBL curriculum to biochemistry teaching. The response options and overall students’ answers for these items were “agree”, “neutral”, and “disagree”. Overall, the response frequency indicated that significant differences (p < 0.05) were observed between the PBL and the non‐PBL groups for the following statements “Hybrid–PBL application to biochemistry” (72.1% of the PBL group agreed compared with 30.1% of the non‐PBL group); “Desire to take a PBL class” (61.3% of the PBL group agreed compared with 29.8% of the non‐PBL group); “Improvements in biochemical knowledge understanding” (60% of the PBL group agreed compared with 31.2% of the non‐PBL group); “Increased initiative to study biochemistry” (75.5% of the PBL group agreed compared with 21.2% of the non‐PBL group); and “Increased ability to solve medical questions in molecular terms” (71.1% of the PBL group agreed compared with 28.9% of the non‐PBL group). No significant differences were observed between the PBL and the non‐PBL groups for the following statements: “Requirements for more PBL training” (86.7% of the PBL group agreed compared with 79.5% of the non‐PBL group, p = 0.117); and “Mainstream pedagogy in medical education” (55.5% of the PBL group agreed compared with 50.9% of the non‐PBL group, p = 0.396).

Evaluation of the Hybrid–PBL curriculum in biochemistry teaching

2 Significant differences between the PBL group and the non‐PBL group.

Consequently, the questionnaire analyses demonstrated that most of the international medical students were inclined to accept the PBL curriculum as a nonmainstream pedagogy for biochemical learning and that the Hybrid–PBL curriculum was an appropriate teaching module for the specific discipline of biochemistry.

A written examination on biochemistry is a requirement for the medical students at DMU. The biochemistry examination, which covers the key points of biochemical knowledge, includes approximately 74 questions that must be answered in 90 min.

The analysis of the biochemistry examination scores revealed a distinct difference between the PBL and the non‐PBL groups when identical questions were applied in the examination (Table [NaN] ). The mean examination score for the PBL group (69.33 ± 17.70) was significantly higher than the mean examination score for the non‐PBL group (62.31 ± 20.90) when the examinations included identical questions. Significant differences in the mean scores were noted between the PBL group (69.90 ± 17.61) and the non‐PBL group (62.25 ± 20.99) when the examinations included different questions.

Comparisons between the examination scores of the PBL and the non‐PBL groups

3 Significant differences between the PBL and the non‐PBL groups.

The international students acquired more biochemistry knowledge by developing their learning issues and listening to the presentations that were given by their classmates in the PBL class. In addition, the discussions in the PBL class allowed the students to review the relevant biochemistry facts. Therefore, the international medical students achieved higher examination scores. Our study confirmed that the international medical students who were trained in the PBL program achieved higher scores on the biochemistry examination than those with training from conventional lecture‐centered modules.

A conventional teaching approach uses theoretical, abstract knowledge to teach practical skills [14] . Generally, teachers who instruct conventional classes directly provide students with certain standard or recommended answers or procedures for learning. In contrast, PBL actively encourages students to express their ideas based on their prior learning and experiences; furthermore, students receive feedback from other members of the group. Therefore, students gain practical value because PBL programs stimulate thinking and help to create an openness to new concepts in the group [15] . Previous studies have demonstrated that PBL graduates are more satisfied with the quality of their education than traditional program graduates [16] and that the PBL method did not place graduates at a disadvantage on standardized, objective tests of knowledge, such as licensing and credentialing examinations [16] . PBL students perform significantly better than their conventional counterparts and graduate with significantly higher mean scores and a higher number of credits in various disciplines [17] . Norman and Schmidt [18] concluded that PBL increases the retention of knowledge, enhances the transfer of concepts to new problems, and improves the intrinsic interest and maintenance of self‐directed learning skills.

Our results revealed that a Hybrid–PBL program for biochemistry teaching enhanced the students’ understanding of biochemical knowledge, increased their initiative to study biochemistry, and helped them to obtain the ability to solve medical questions in molecular terms. In this study, most of the international medical students preferred to receive a more PBL‐based curriculum for biochemistry learning. Our results were consistent with prior studies regarding medical education, and PBL programs are generally acceptable and satisfactory for medical education. This study provides a new perspective on biochemistry teaching, and the Hybrid–PBL module is promising and can be applied to other medical educational fields such as physiology or pathophysiology.

At UCLA, medical students obtain a bachelor's degree in biology or another relevant field prior to enrolling in medical education. Accordingly, the majority of these medical students possessed excellent background knowledge in life science. The medical students at UCLA were highly and actively involved in the PBL class and had positive discussions there; they made a preliminary diagnosis, used their reasoning and judgment and relied on the patient's information. In contrast, most international medical students who study in China have only graduated from high school, and these students were generally academically weak in their performance in the PBL class, had less basic knowledge of life science, had fewer prior experiences, and had less interest in the learning approaches. The diversity in the students’ educational backgrounds was a major factor in determining their academic performance in the PBL class. Student performance in the PBL class depended primarily on their basic knowledge of life science and their previous experiences; the deficient educational backgrounds directly led to unsatisfactory academic performance when the PBL approach was used. Based on the shortcomings of the Chinese students regarding educational backgrounds, we modified the PBL cases to suit the teaching program to their abilities in the study of medical biochemistry.

For years, PBL has been used in multidisciplinary settings that include a comprehensive array of basic clinical knowledge. The general goals of PBL are to help students to acquire professional knowledge, improve self‐directed learning, gain effective collaboration skills, obtain intrinsic motivation for learning, acquire effective problem solving skills and to teach students how to think like a clinician. We applied the PBL curriculum to medical biochemistry, a specific disciplinary setting. Therefore, the PBL curriculum was expected to help international medical students to better understand lectures, timely review lecture content, and increase their enthusiasm and interest in learning biochemistry. Because of the depth and range of the PBL cases that were used in this study, it was impossible to reach identical conclusions regarding multidisciplinary PBL settings. This Hybrid–PBL program that was used in a specific disciplinary setting was well accepted. In this study, the case content was easily understandable and was closely related to the biochemistry lectures. In addition, the Hybrid–PBL class could be conducted freely after the lectures to efficiently strengthen biochemistry knowledge. Although the multidisciplinary PBL curriculum was much more successful in building a firm foundation for medical students, the specific disciplinary setting of PBL in biochemistry helped students to understand complex knowledge and basic science.

To improve the teaching effects and to help medical students obtain an improved understanding of biochemistry to improve their clinical competence, we focused on optimizing the PBL cases for the specific discipline of biochemistry and on preparing more applicable biochemistry PBL cases for the future. A modified Hybrid–PBL program for the specific discipline of biochemistry at DMU is in its exploratory phase. Regarding the optimization of the design of the PBL cases, the simple biochemistry cases, which are straightforward and highly relevant to the content of biochemical knowledge, are, by nature, superior choices. Another concern regarding this curriculum reform is ascertaining the time‐course of the Hybrid–PBL curriculum. In this study, the PBL class was successfully performed after its corresponding lecture. Although the increased effectiveness of biochemistry learning was achieved from the current Hybrid–PBL module, in the future, we plan to attempt a complicated biochemical PBL case after all biochemical lectures have finished. An improved PBL time‐course in biochemistry teaching will be determined by comparing the learning effectiveness of the PBL class with different time‐courses. It is our hope that the trial of the current Hybrid–PBL program can help medical students develop a deeper understanding than is possible with lectures, focus on reinforcing textbook knowledge, and acquire biochemistry knowledge with enthusiasm and interest.

Although the Hybrid–PBL curriculum was well accepted according to the feedback from the international medical students, certain issues should be seriously considered and improved in the future. Some areas for improvement include optimizing the internet resources that are available to the PBL program, requiring an exclusive classroom for the PBL program, requiring a more experienced facilitator specifically for the PBL program, and increasing publicity of the PBL program's processes and objectives to medical students.

In this study, we successfully conducted a teaching reform in the biochemistry courses at DMU in China by introducing a Hybrid–PBL teaching program that combined a PBL curriculum with conventional lectures. As a consequence, the reformed Hybrid–PBL teaching program was determined to positively affect the students’ learning in the specific disciplinary setting of biochemistry according to a survey that was completed by the international medical students who study at DMU. The international medical students acquired more abilities from the Hybrid–PBL curriculum and achieved higher scores on the biochemistry examination than from conventional teaching methods. Currently, the Hybrid–PBL classes are well accepted by the international medical students as an effective supplement to lecture‐centered teaching programs and are an effective tool to objectively improve knowledge acquisition in medical teaching. Our study was an innovative trial that applied a PBL curriculum to a specific discipline under basic conditions. As we know, there is no previous similar study of hybrid PBL to teach biochemistry for international medical students in China till now. This successful experience provides a perspective regarding the universal use of PBL curricula in many fields.

This study was supported by grant number PJHYYB15142 from the first session of the Educational Evaluation Association of Liaoning Province, grant number DYLX15005 of DMU, and grant number [2013]1113 of the National Brand Curricula of International Students Teaching in English. We extend special thanks to the David Geffen School of Medicine at UCLA for allowing us to use their educational training on the PBL curriculum for 3 months.