Commentary: The promise of problem‐based learning

Physicist Leo Szilard once said “An optimist is someone who believes the future is uncertain. ” With the possibility for change, there is hope and motivation. The fact that change can be for better or worse provides the incentive to work for the better. For an optimist, belief implies commitment to some set of principles and a vision of a better future. Teachers are optimists. What teacher does not know the profound frustration of poor student performance? How could this happen when the lectures and text were so clear (to us)? For students, such experiences can cultivate pessimism with low expectations and apathy. Teachers of science frequently explain poor student performance in the following ways: they have an inadequate background, are not very bright, do not know how to study, or party too much. While all of these explanations may apply to some groups or individuals, do they absolve teachers of a share in the responsibility for poor performance? Should optimists cultivate pessimists? Most readers of this commentary would profess an inability to draw well. Few of us practice this skill beyond grade school. Imagine yourself in a drawing class with a teacher whose goal was to teach you and everyone else in the class to draw well. How much would your conviction that you cannot draw well inhibit the expression of your innate drawing ability? In Drawing on the Right Side of the Brain [1], Betty Edwards claims to teach 95% of her students to draw well. Her book was on the New York Times best seller list for more than a year and sold over 2.5 million copies. Through the use of unusual exercises, she enabled students to see things differently and was able to get them to draw well. Betty Edwards’ book is about learning and is one of the most optimistic books I have ever read. It fueled my hope that that maybe there was a better way to teach biochemistry so that more students would understand and appreciate the subject. It laid the groundwork for considering alternative means to a better end. Problem-based learning (PBL) provides an alternative to traditional lecture-based education. It claims to mimic the way we learn naturally when we confront problems. In principle, PBL reverses traditional education by putting the problem first and using it to motivate learning. By using real-world problems, PBL enables students to see the relevance they often miss in other contexts. The promise of PBL was that students would learn better, understand what they learned, and remember longer by working cooperatively on interesting, challenging problems. Furthermore, PBL promised that students would be actively involved, enjoy the process, and gain important communication skills while becoming life-long learners. What optimism! Like a frictionless wheel, the ideal of PBL is fiction. However, it provides a useful template and vision. When working well, PBL does transform students in the ways intended and enables students to achieve beyond their expectations. Similarly, PBL can be implemented poorly and fail. There is risk in trying new things. When PBL is imposed administratively or implemented without adequate faculty preparation or commitment, things can go wrong [2]. Even under ideal situations, adopting PBL usually means teaching in unfamiliar ways, negotiating issues beyond course content, and dealing with skeptical colleagues. However, the promise of optimists cultivating optimists is a powerful source of motivation. Meta-analyses evaluating 20 years of publications on PBL in medical schools [3, 4] showed that students perform as well and sometimes better on clinical examinations and faculty evaluations but less well on certain board examinations. While one might hope for a clear difference in medical knowledge, significant positive effects of PBL may lie elsewhere in better critical thinking skills, increased curiosity, the ability to locate relevant information efficiently, and improved communication skills. Assessment has been a challenge because PBL includes more than content objectives. Ultimately our goal is to have our students become responsible, contributing members of society. Because PBL deals with process issues beyond content, one would hope PBLtrained students would benefit in tangible ways toward this goal. Will we discover 50 years from now that PBL-trained physicians were sued less often or that a disproportionate number of PBL-trained students became educators? The future is uncertain, but the promise is there.