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JAOA • Vol 107 • No 10 • October 2007 • 443-449
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MEDICAL EDUCATION

Lake Erie College of Osteopathic Medicine's Preclinical Problem-Based Learning Pathway Program: An Alternative Medical School Curriculum Design

 Silvia M. Ferretti, DO; Wayne A. Krueger, PhD; Lawrence L. Gabel, PhD; John J. Curry, PhD

From the Lake Erie College of Osteopathic Medicine in Erie, Pa (Dr Ferretti) and in Bradenton, Fla (Dr Krueger); and from The Ohio State University (Drs Gabel and Curry) in Columbus.

Address correspondence to Lawrence L. Gabel, PhD, The Ohio State University, Department of Family Medicine, B0902B Cramblett Hall, 456 W 10th Ave, Columbus, OH 43210-1240. E-mail: gabel4{at}osu.edu

In 1999, the American Osteopathic Association approved plans for "substantive change" to the medical curriculum at Lake Erie College of Osteopathic Medicine (LECOM) in Erie, Pa. In addition to the school's traditional, lecture-based curriculum, LECOM sought to create alternative—but distinct—learning pathways: independent study (described elsewhere) and problem-based learning (PBL). After selecting a long-standing, successful PBL program to guide our efforts and after a 1-year period of planning, developing, piloting, and refining the program, we introduced PBL in the 2000-2001 academic year. This learning pathway consists of carefully constructed cases that allow for progressive disclosure across group-tutorial sessions, from patient presentation to diagnosis and management. With more than 5 years of data on student performance and evaluations, LECOM can investigate the merits of its three basic science learning pathways. The description of LECOM's longitudinal database will allow program evaluators to assess and compare each of the three basic science learning pathways.

The Lake Erie College of Osteopathic Medicine (LECOM) in Erie, Pa, received full accreditation status from the American Osteopathic Association (AOA) with its first graduating class in 1997. The school's preclinical basic science curriculum at the time of its inception was based on a traditional lecture-discussion learning pathway. In 1999, the AOA Council on Predoctoral Education approved LECOM's request to develop and implement two additional, "alternative" preclinical curricular pathways: independent study1 and problem-based learning (PBL).

Each pathway concentrates on a specific element of learning. The traditional learning pathway is characterized by large-group lectures and structured laboratory experiences interspersed with teacher-directed class assignments. Conversely, the independent study pathway is minimally structured and allows students to learn at a self-determined pace.1 Problem-based learning consists of clinical cases reviewed by students in small groups. These small groups are facilitated by at least one faculty member and identify group-derived learning issues (eg, areas that highlight a knowledge deficit).2-4 Key features of each learning pathway are presented in Figure 1. All three pathways are distinct but equal in overall learning outcomes.


Figure 1
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  		Figure 1. Key features of the three learning pathways available at Lake Erie College of Osteopathic Medicine in Erie, Pa. Pathways are available in the first and second years of osteopathic medical education.

 
Like independent study and traditional learning pathways, PBL is a unique alternative curricular pathway offered in a stand-alone fashion. In PBL at LECOM, elements of the science content in the first year (Figure 2) are revisited in the second year (Figure 3). Format and delivery of other courses (eg, osteopathic principles and practice, clinical examination) vary and are not specific to independent study or PBL because all students, regardless of learning pathway, participate in these courses together.


Figure 2
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  		Figure 2. Problem-based learning pathway curriculum for first-year students. When the content areas listed are studied in conjunction with a problem-based learning case, the learning issues selected by the group should include all relevant basic sciences associated with that topic. Basic sciences include anatomy, biochemistry, embryology, histology, immunology, microbiology, molecular biology and genetics, neuroanatomy, pathology and pathophysiology, pharmacology, and physiology and cell biology.

 

Figure 3
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  		Figure 3. Problem-based learning pathway curriculum for sophomore students. When each of the content areas listed are studied in conjunction with a problem-based learning case, the learning issues selected by the group should include all relevant basic sciences associated with that topic. Basic sciences include anatomy, biochemistry, embryology, histology, immunology, microbiology, molecular biology and genetics, neuroanatomy, pathology and pathophysiology, pharmacology, and physiology and cell biology.

 

The current study summarizes the means used to introduce PBL at LECOM, describes key elements of implementing PBL, and presents a scheme to evaluate PBL outcomes compared with those achieved through the traditional and independent-study1 learning pathways. In providing all aspects of LECOM's PBL program implementation, the current study responds to criticisms of Sheets and Anderson5 that only 12% of articles describing curricular development include all of the steps taken to develop the curriculum, and only 29% of such articles describe all essential components of the curriculum.


   Program Development
Top
 Program Development
Program Implementation
 Program Evaluation
 Comment
 Conclusion
 References
 
When institutionalizing a new educational program, there are three distinct choices: de novo development, which typically requires significant financial and personnel resources; carte blanche adoption, though seldom is there a perfect match from one institution to another; and selective adaptation, a compromise between these two models. The selective adaptation approach was chosen for LECOM so that the PBL pathway would be operational within 1 year. After examining a number of existing programs, we chose to base our model on the problem-based learning program at The Ohio State University in Columbus. Figure 4 summarizes LECOM's adaptation process, including AOA approval for "substantive change,"6 and provides an overview of the steps taken and their approximate times for completion.


Figure 4
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  		Figure 4. Outline of the process of adapting a problem-based learning (PBL) program for Lake Erie College of Osteopathic Medicine (LECOM) in Erie, Pa, based on a model used by The Ohio State University in Columbus. Lines indicate approximately when specific steps began and when they were completed. Steps that did not span a number of months (ie, were completed within 1 month) are indicated by X. Abbreviation: AOA, American Osteopathic Association.

 

   Program Implementation
Top
 Program Development
 Program Implementation
Program Evaluation
 Comment
 Conclusion
 References
 
Problem-based learning in medical education supports four primary goals:

Similarly, passive learning of information in PBL is almost completely eliminated.

At LECOM, PBL enrollment is limited to 40 students per year. Groups consist of eight students and one faculty facilitator (basic science instructors work with first-year student groups, and clinical science instructors oversee sophomore groups). Facilitators' primary group-related responsibilities are to distribute course-related materials and nurture discussion. A series of clinical cases (presented in modules, one case per module) serves as a basis for learning the basic sciences during these 2 preclinical years. Approximately 31 cases are presented each year to first-year student groups and between 37 to 39 cases are presented to sophmore groups. Although first-year student groups originally met 3 times per week and sophomore groups met twice weekly, both groups currently meet 3 times per week for 2 hours per session.

With each clinical case, the objective is not to diagnose but rather to identify learning issues, which provide students with a basis for independent study before the group meets again. Learning issues are topics that students do not understand while discussing a case during a group session. The students recognize that they need to better understand these topics (ie, increase their knowledge in the basic sciences) to proceed logically through cases. For example, a student might identify "the cardiac cycle" as a learning issue so that they could fit "heart sounds" into a meaningful context when they are mentioned in a case. In each successive session, students share new information, discuss the case, and identify additional learning issues based on continued progressive disclosure of the case by the facilitator as well as the group's related discussions. Each case is discussed in at least two sessions, but some cases may require additional sessions depending on students' familiarity with the topics at hand.

Students' knowledge, originally tested every 5 weeks, is currently tested every 6 to 7 weeks using board-style examinations, comprising multiple-choice and matching questions. Faculty members submit test questions to a test-writing committee. Although questions are different each year, many questions are identical among groups in any one examination, which allows for intergroup comparisons. Some questions may be different if unique learning issues were identified by different groups.

At the end of each semester, each group of students and its facilitator evaluate each other regarding group process. At the beginning of the next semester, the groups are reconstituted with different membership and a balance of student gender and past performance.

Cases
Each PBL case is based on physicians' real experiences with patients and comprises health-related problems and clinical information from the time the patient first visits a physician continuing through associated diagnostic and disease-management processes. Cases are organized in a modular format based on discrete "blocks" of information (Figure 5). Each block of information (eg, "Patient Presentation," "Initial Clinical Interview," etc) is printed on a separate sheet of paper that facilitators can distribute to students as needed. In most cases, information is presented in approximately the same sequence as would become available to a practicing physician over time. However, student discussion of the case and their readiness for specific information ultimately determines when it will be disclosed.


Figure 5
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  		Figure 5. Standard format of each module of the problem-based learning pathway at Lake Erie College of Osteopathic Medicine in Erie, Pa. Each block of information is printed on separate sheets of paper, which allows facilitators to distribute discrete amounts of information from the module at any given time. "Additional Patient Information" may consist of several blocks of information, and therefore, that information would appear on separate sheets of paper. *Anecdotal patient names are assigned for all cases.

 
Group-Tutorial Process
At the first group-tutorial session, regardless of semester, students and facilitators briefly introduce themselves. This provides an opportunity for all to gain a common understanding of expertise within the group and any potential factors that might affect group process (eg, students in a group with someone who has a pharmacy degree and work experience may expect him or her to explain a pharmacy-related learning issue without looking up the information for themselves). At this first session and in all subsequent sessions when a new case is introduced, specific responsibilities are assigned, chosen, or volunteered depending on how the group has decided to operate. The "scribe" records information on a "blackboard" as the case unfolds, a "reader" reads each page of information as it is distributed, and a "patient" and "physician" role-play the process of taking the oral history. Roles are rotated with each case.

The group-tutorial process can be divided into three phases. In the first phase, the reader reads each page as it is distributed while the scribe records information gleaned from the reading. The blackboard is divided and labeled according to various headings (eg, "facts," "general ideas," "questions," "hypotheses," and "learning issues"). The students first discuss the facts and determine which are important and which are irrelevant, and then they probe for scientific explanations and correlative information relating to the clinical picture that emerges. Group members use their existing knowledge to initiate discussion. In addition, students are also encouraged to look up additional information in available resources (eg, books brought by individual students, the Internet).

Learning and understanding the basic science mechanisms associated with clinical symptoms and signs—not diseases—is the primary goal of PBL. This goal—not "making a diagnosis"—must constantly be maintained throughout the group-tutorial process. It is also important to the learning process to maintain an "osteopathic" approach and to assess any osteopathic learning issues that may be relevant to each case.

Facilitators should always encourage students to challenge each other—and the information presented regarding basic accuracy and their own understanding. With regard to group dynamics, it may be difficult in the early stages of the process for students to challenge—and be challenged by—others in a constructive manner. Initially, they may feel personally insulted by such challenges. However, as students' clinical and interpersonal skills and their familiarity with each other increases, we have found that these challenges usually become an enjoyable aspect of the process and help students—individually and collectively—focus on areas where knowledge must be gained.

As the number of items listed in the various headings grow and as the process is repeated through the subsequent distribution of blocks of information, students begin to formulate testable hypotheses. To do this, students predict what might be on the next page or pages by asking questions such as:

In the process, learning issues are identified. Learning issues should be selected by the group in response to the need to answer a general question. Specific questions such as "What does the first heart sound represent?" are not as helpful in determining learning issues as a more general topic. For example, a more global topic related to "all heart sounds" or "the cardiac cycle" would be more appropriate. In addition, learning issues should be relatively complete topics representing a body of information within which the answer to a specific question related to the learning issue can be found (eg, a specific chapter of a textbook).

At the conclusion of each session, the group decides which learning issues to pursue and which resources might be the most useful. Also, time should be allotted for students and facilitators to evaluate the session (eg, what was beneficial, what might have made the session more productive).

During the second phase, the students independently address the learning issues adopted at the conclusion of the preceding group session. In other words, students engage in independent study by using resources such as textbooks, journals, microscope slides, radiographs and other scans, audio-visual materials, the Internet, and even faculty to learn information regarding previously determined learning issues. Students are encouraged to work together, and communication between and among members of different tutorial groups is allowed.

During the third phase, which occurs at the next scheduled group-tutorial session, students share and discuss what each has learned. Students then use their new knowledge to evaluate previously posited hypotheses. Often the session begins with a student—selected or volunteer—presenting the case as it was left in the last session as though presenting to an attending physician.

In light of new information, the students continue discussing the case, list new ideas, formulate new hypotheses, and identify new learning issues. This is followed by another group self-evaluation at the end of the session, another period of independent study, and additional group-tutorial sessions, as necessary. This process is repeated until the students are satisfied that they have gained sufficient knowledge of the basic scientific concepts that are necessary to understand the mechanisms underlying the clinical picture presented in the case. Subsequently, the group evaluates its activities, summarizes what has been learned, and determines which learning issues to submit to the PBL administrative office for possible inclusion in future testing.


   Program Evaluation
Top
 Program Development
 Program Implementation
 Program Evaluation
Comment
 Conclusion
 References
 
Students' test results and other measures of progress (eg, facilitator and peer evaluations) through the curriculum are monitored, assessed, and evaluated for trends that might indicate needed modifications to the PBL pathway. Processes and strategies for evaluation are identical to those used in the traditional and independent study learning pathways. For example, students in each of the three basic learning pathways are tested on a regular basis on established amounts of material (Figure 1). All students (ie, first-year and sophomore students in all three learning pathways) complete questionnaires regarding their satisfaction with their respective learning pathways. Quantitative and qualitative responses are summarized and reported to the institutional committees responsible for the curriculum and student performance. All sophomores, regardless of designated learning pathway, are required to pass the Level 1 Comprehensive Osteopathic Medical Licensing Examination.

As previously indicated, we intend the three basic science learning pathways to be equivalent regarding graduates' summative competencies. Over time, and with confounding variables removed, we expect no significant differences in comparisons of group-based performance regardless of curricular pathway. To position ourselves to assess this expectation, we have developed parameters for a longitudinal database (Figure 6). As resources allow, we are populating the database with data collected since students first graduated from LECOM in 1997. The longitudinal database will soon be a viable resource for a variety of studies relative to LECOM's three basic science learning pathways. We are committed to comparative studies of any combination of learning pathways only if data is available for 5 years of any given learning pathway.


Figure 6
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  		Figure 6. Data fields in the longitudinal database at Lake Erie College of Osteopathic Medicine (LECOM) in Erie, Pa. Data collection will be used to compare the three learning pathways currently used at LECOM: traditional lecture-discussion, independent study, and problem-based. Abbreviations: GPA, grade point average; CE, clinical evaluation; COMLEX-USA, Comprehensive Osteopathic Medical Licensing Examination; MCAT, Medical College Administration Test; PE, performance evaluation; PGY-1, first year of postgraduate training; PGY-2, second year of postgraduate training.

 
Much interest in such studies exists as evidenced by three landmark reviews2,4,9 that examined the effectiveness of PBL compared with traditional learning. Few studies exist of a similar nature regarding comparing the independent study pathway and the traditional pathway; we found two.3,10 Studies comparing PBL and independent study or PBL, independent study, and traditional study are not available, and, of all studies found regarding medical education learning pathways, the number reported in the osteopathic medical education literature is minuscule.1,11


   Comment
Top
 Program Development
 Program Implementation
 Program Evaluation
 Comment
Conclusion
 References
 
Adoption of PBL into medical school curricula has been a worldwide phenomenon. After its introduction in the mid-1960s at McMaster University in Hamilton, Ontario, Canada,12 an estimated 60 medical schools worldwide had espoused PBL in whole or in part by the early 1990s.13 By 2000, an estimated 10% of medical schools worldwide had adopted PBL in some form.14 Not surprisingly, PBL has been described as one of the most comprehensive innovations in medical education since the Flexner Report.2,15 While PBL curricula tend to occur most frequently in the first 2 years of medical education, numerous examples exist of PBL in the final 2 years of medical school.16-20

Given the growing prevalence of PBL as a learning pathway, it is not surprising that medical education literature demonstrates longstanding interest in whether differences exist between students who complete PBL pathways compared with those in traditional lecture-discussion pathways. The most frequently questioned and compared elements include attitudes, basic and clinical science knowledge, and clinical competencies.21-23

Although most studies21-27 report data favoring PBL over traditional learning pathways, some studies favor the traditional learning format over PBL,28-30 particularly when basic science examinations are being compared. However, some studies21,23 may have been conducted prematurely, involving only the first few classes to complete PBL at the particular school where the study was conducted. As a result, studies comparing the three pathways at LECOM will not be made until at least 5 years' worth of data is available for analysis.

Two studies3,10 comparing the independent study and traditional learning pathways support these plans. The studies,3,10 which were conducted at the same institution and were based on 10 years of data, reported that student outcomes of the two programs were more alike than different. Specifically, students pursuing the independent study program and students in the more traditional program performed similarly on Part I of the National Board of Medical Examiners tests and in the required clerkships.3,10 These studies also reinforce our expectation that LECOM's three distinct basic science learning pathways will be similar in students' overall learning outcomes.

The current study has discussed three key elements of curricular program development: (1) the means used at LECOM to introduce a PBL pathway in the first 2 years of medical school, (2) PBL as we have implemented it at LECOM, and (3) a longitudinal database to be used to evaluate PBL outcomes and to compare with those of the lecture-discussion and independent study learning pathways. The longitudinal database has positioned LECOM to study problem-based, independent study, and traditional learning pathways in various combinations regarding implementation and outcome issues.


   Conclusion
Top
 Program Development
 Program Implementation
 Program Evaluation
 Comment
 Conclusion
References
 
The PBL pathway at LECOM allows students to participate in a combination of small group and independent study activities. Students' studies are based on learning issues defined by their respective small groups as a result of collective work on cases presented in a modular format. A major goal of this pathway is to provide medical students with rigorous learning opportunities in a less structured environment than normally possible with the more traditional curricular pathway. The PBL pathway is more similar to the environment that they will experience as competent, life-long, self-directed learners. It is expected that future studies comparing LECOM's three learning pathways—traditional, independent study, and problem-based—will reveal their value in osteopathic medical education.


   Acknowledgment
 
The authors gratefully thank PBL Program Director W. Richard Chegwidden, PhD, FRSC, at LECOM in Erie, Pa, for advice and counsel to ensure that the descriptive elements of the article were both accurate and current.

Submitted July 28, 2004; revision received March 3, 2006; accepted March 13, 2006.


   References
Top
 Program Development
 Program Implementation
 Program Evaluation
 Comment
 Conclusion
 References
 
1. Ferretti SM, Mesina JE, Gabel LL. Lake Erie College of Osteopathic Medicine's independent study pathway program: an alternative medical school curriculum design. J Am Osteopath Assoc. 2000;100:713-716. Available at: http://www.jaoa.org/cgi/reprint/100/11/713. Accessed September 14, 2007.

2. Albanese MA, Mitchell S. Problem-based learning: a review of literature on its outcomes and implementation issues [published correction appears in Acad Med. 1993;68:615]. Acad Med.1993; 68:53 -81.

3. Trzebiatowski GL, Williams JH, Sachs LA, Altman M, Bellchambers M. Independent study: 10-year programme review. Med Educ.1987; 21:458 -463.[Medline]

4. Vernon DT, Blake RL. Does problem-based learning work? A meta-analysis of evaluative research. Acad Med.1993; 68:550 -563.[Medline]

5. Sheets KJ, Anderson WA. The reporting of curriculum development activities in the health professions. Teach Learn Med.1991; 3:221 -226.

6. Commission on Osteopathic College Accreditation. Accreditation of Colleges of Osteopathic Medicine: COM Accreditation Standards and Procedures. 2007. Available at: https://www.do-online.org/pdf/acc_predocomstds.pdf. Accessed October 9, 2007.

7. Barrows HS. A taxonomy of problem-based learning methods. Med Educ. 1986;20:481 -486.[Medline]

8. Dwinnell BG, Adams L. Problem-based learning in medical education. Hospl Pract (Minneap).1998; 33:15 -17.

9. Berkson L. Problem-based learning: have the expectations been met [review]? Acad Med.1993; 68(suppl 10):S79 -S88.[Medline]

10. Sachs LA, Altman M, Trzebiatowski GL, Williams JH, Verny R, Bellchambers M. A comparison of medical students' performances in independent study and traditional programs. J Med Educ.1985; 60:602 -609.[Medline]

11. Chegwidden WR. A problem-based learning pathway for medical students: improving the process through action research. Ann Acad Med Singapore. 2006; 35:642 -646.[Medline]

12. Problem-based learning, especially in the context of large classes page. McMaster University Web site. Available at: http://www.chemeng.mcmaster.ca/pbl/pbl.htm. Accessed September 26, 2007.

13. Norman GR, Schmidt HG. The psychological basis of problem-based learning: a review of the evidence. Acad Med.1992; 67:557 -565.[Medline]

14. Chalon P, Delvenne C, Pasleau F. Problem-based learning, description of the pedagogical method leading to evidence-based medicine [in French]. Rev Med Liege.2000; 55:233 -238.[Medline]

15. Flexner A. Medical education in the United States and Canada. New York, NY: Carnegie Foundation for the Advancement of Teaching; 1910. Available at: http://www.carnegiefoundation.org/files/elibrary/flexner_report.pdf. Accessed September 28, 2007.

16. Gresham CL, Philp JR. Problem-based learning in clinical medicine. Teach Learn Med.1996; 8:111 -115.

17. McGrew MC, Skipper B, Palley T, Kaufman A. Student and faculty perceptions of problem-based learning in a family medicine clerkship. Fam Med. 1999;31:171 -176.[Medline]

18. Cooksey JA, Danziger LH, Ervin NE, Groves SL, Tyska C, Kirk G. Problem-based learning in an interdisciplinary community-based primary care course. Teach Learn Med.1995; 7:241 -245.

19. Cleave-Hogg D, Gare D. Development of a problem-based obstetrics and gynecology curriculum for 3rd-year medical students. Teach Learn Med. 1995;7:95 -101.[Medline]

20. Wendelberger KJ, Simpson DE, Biernat KA. Problem-based learning in a third-year pediatric clerkship. Teach Learn Med.1996; 8:28 -32.

21. Kaufman DM, Mann KV. Comparing students' attitudes in problem-based and conventional curricula. Acad Med.1996; 71:1096 -1099.[Medline]

22. Blake RL, Hosokawa MC, Riley SL. Student performances in Step 1 and Step 2 of the United States Medical Licensing Examination following implementation of a problem-based learning curriculum. Acad Med. 2000;75:66 -70.[Medline]

23. Distlehorst LH, Robbs RS. A comparison of problem-based learning and standard curriculum students: three years of retrospective data. Teach Learn Med.1998; 10:131 -137.

24. Distlehorst LH, Dawson E, Robbs RS, Barrows HS. Problem-based learning outcomes: the glass half-full. Acad Med.2005; 80:294 -299.[Medline]

25. Goodyear HM. Problem based learning in a junior doctor teaching programme. Arch Dis Child.2005; 90:275 -278.[Abstract/Free Full Text]

26. Iputo JE, Kwizera E. Problem-based learning improves the academic performance of medical students in South Africa. Med Educ. 2005;39:388 -393.[Medline]

27. Gurpinar E, Musal B, Aksakoglu G, Ucku R. Comparison of knowledge scores of medical students in problem-based learning and traditional curriculum on public health topics. BMC Med Educ.2005; 5:7 .[Medline]

28. Jones JW, Bieber LL, Echt R, Scheifley V, Ways PO. A problem-based medical curriculum—ten years of experience. In: Schmidt HG, de Volder ML, eds. Tutorials in Problem-Based Learning. Masstricht, The Netherlands: Van Gorcum; 1984:181 -198.

29. Farquhar LJ, Haf J, Kotabe K. Effect of two preclinical curricula on NBME Part 1 examination performance. J Med Educ.1986; 61:368 -373.[Medline]

30. Kaufman A, Mennin S, Waterman R, Duban S, Hansbarger C, Silverblatt H, et al. The New Mexico experiment: educational innovation and institutional change. Acad Med.1989; 64:285 -294.[Medline]





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