What are cases?

The use of cases is as old as storytelling itself. It is instruction by the use of narratives - stories - about individuals facing decisions or dilemmas. Learners engage with the characters and circumstances of the story. They work to identify problems and to connect the meaning of the story to their own lives. The instructor encourages exploration of the case and consideration of the characters' actions in light of their own decisions.

What is case-based learning?

The case study approach builds on these principles and formalizes them, with variations to suit the subject matter (Boehrer and Linsky, 1990). Cases have traditionally been used to teach decision making skills in professional education, as exemplified in the Harvard Business School case approach (Christensen and Hansen, 1987). More recently, cases are being used for learning medical science (Wilkinson and Feletti, 1989, Tosteson, et al., 1994) in a model called problem-based learning or PBL (Barrows and Tamblyn, 1980). The medical school use of cases differs from that in other professional schools in that PBL focuses on medical subject matter content more so than on decision-making.

What is unique about the BioQUEST cases and the ICBL(investigative case-based learning) approach for science learning?

As in all case-based learning, the problem space is defined by the case. However, students are not asked only to learn new material, but to pose a question, develop accountable approaches to investigate the question and present methodology and conclusions to the class that support a reasonable answer to their question. What sets this approach and cases featured here apart from previous case work is an emphasis on research-like environments for learning biology.

Lessons from problem based learning in medical education:

Our approach to case study grew out of experience with medical case-based PBL. Some elements of that approach are extremely useful and are retained in the investigative case study approach..

1. Cases are based on realistic and meaningful problems, they are multidisciplinary

In the case study approach students learn biology in the context of realistic situations. They have practice using biological information to investigate and come to resolution on complex problems. Since learning occurs around a particular realistic problem, there is greater likelihood that the learned material will be better retained and more easily applied to similar situations (Brown et al., 1989, Schmidt, 1983). In their lives they may never face the exact problems they study, however, they will have experienced using scientific knowledge and scientific thinking to work out reasonable solutions.

2. The case defines a problem space

In case-based PBL, the problem is used in a different fashion than problems are traditionally used for science learning. In PBL the case defines a problem space that learners will investigate. In case-based PBL, the case problem comes first in the instructional sequence. This is a reversal of the usual use of problems in science teaching. By putting the case early in the instructional sequence, the learners use the case to brainstorm a set of questions they will try to answer. They thus become more directed in their reading and more motivated in subsequent lectures, labs, and discussions. In fact, they are learning in just the way most of us learn-- because they have a problem or question of their own to work on.

Faculty members choose cases or write their own, and so draw the boundaries on the problem space. The case defines a problem space in much the same way that the lines on a soccer field defines a playing space. As in soccer, the case sets some limits on the area of subject matter to be explored. And as in soccer, once the game has begun, the players move over the playing field moving in general directions, and with goals, but not in a prescribed linear manner. Unlike soccer, it's ok to go out of bounds for a while with a case, as long as the general direction and goals are attained.

3. Students make decisions about their learning, and

4. Some phases of case study are best done collaboratively

Commonly in the medical case-based PBL approach, students work in groups of 8-10 with a "tutor," meeting to discuss a case based on a real patient or situation (Fig. 2). Students read part of the case out loud, then discuss the elements presented thus far in the case. They generate hypotheses, list their outstanding questions, and develop a learning agenda -- issues they agree to pursue before their next meeting. This phase of case study is one in which students are actively engaged and working together to brainstorm issues, share what they know, and develop their plans for learning.

Some possible learning issues from the Ben Brown case: Access to health care, causes of coughs, parts of the body involved in breathing and coughing, the blood supply of the lungs, homelessness, universal precautions.

5. The faculty member becomes more of a guide to methodology than an information source.

As you consider case-based learning in the classroom, think about what a case discussion might look like with a small group. The "instructor" has several roles (though to the student eye it may seem he does little): facilitates discussion, helps students explore their thinking and reasoning without leading them, and helps with group dynamics. During case discussions, students are actively engaged in interpreting the case, proposing problems and possible solutions, brainstorming, and using resources. At Harvard Medical School the faculty and students agree that the chalkboard belongs to the student during case discussions. Students take on roles we commonly think of as teacher roles: deciding what to focus on, developing questions, leading the discussion, using the board to keep notes, make drawings, or list learning issues. Resources to support student learning are frequently in the room - books, images, computer access to the Internet, computer simulations, models, etc.