The use of PBL in various settings has revealed both advantages and disadvantages. Gallagher et al. (1995) view PBL as mimicking real-life situations and being inherently interdisciplinary, which allows the student to perceive how different disciplines interact when problem solving. Through the careful process of coaching and modeling, teachers empower students to become self-directed and independent learners, capable of approaching the kinds of complex problems they will face as professionals.
Problem-based learning students may not perform as well on multiple-choice tests as students taught by lecture-based instruction; however, follow-up studies completed by Norman and Schmidt (1992) reveal better long-term knowledge retention for PBL students. The apparent improvement in retention may be connected to the way learning occurs in PBL. Problem-based learning has the potential to structure knowledge so that acquisition and recall are optimized, students develop self-directed learning skills, and there is an increase in the motivation for learning (Bayard, 1994).
Boud and Feletti (1991) warn that a major problem with evaluating PBL programs is that valid acceptable measures of the outcomes of PBL curricula are hard to find or difficult to interpret. Problem-based learning is also difficult to quickly assess and analyze through testing. Multiple-choice questions, the preferred mode for standardized testing, are not readily adapted to measuring the process skills needed for critical thinking. Structured short-answer questions have the ability to measure problem-solving abilities as well as knowledge recall, but are more time consuming to develop and score (Bayard, 1994).
Time spent in study outside of class is a factor of concern to both instructors and students alike. Whether PBL is an advantage or disadvantage depends on the perspective of the individual. When time spent out of class was analyzed in