Case-based learning

What is case-based learning?

Cases are factually-based, complex problems written to stimulate classroom discussion and collaborative analysis. Case teaching involves the interactive, student-centered exploration of realistic and specific situations. As students consider problems from a perspective which requires analysis, they strive to resolve questions that have no single right answer.

Using a case-based approach engages students in discussion of specific situations, typically real-world examples. This method is learner-centered, and involves intense interaction between the participants. Case-based learning (CBL) focuses on the building of knowledge and the group works together to examine the case. The instructor's role is that of a facilitator and the students collaboratively address problems from a perspective that requires analysis. Much of CBL involves learners striving to resolve questions that have no single right answer.

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.

The case study approach builds on these principles and formalizes them, with variations to suit the subject matter. Cases have traditionally been used to teach decision making skills in professional education. More recently, cases are being used for learning medical science in PBL. 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.

• Case-based learning is also a subfield of artificial intelligence. Case-based learning as technology can be found in advanced systems like ITS, e.g. to find stories to support reasoning (Jonassen & Hernandez-Serrano, 2002)

Why use CBL?

• In their effort to find solutions and reach decisions through discussion, students sort out factual data, apply analytic tools, articulate issues, reflect on their relevant experiences, and draw conclusions they can relate to new situations.
• In the process, they acquire substantive knowledge and develop analytic, collaborative, and communication skills.
• Cases add meaning by providing students with the opportunity to see theory in practice.
• Students seem more engaged, interested, and involved in the class.
• CBL develops students' skills in group learning, speaking, and critical thinking.
• Since many cases are based on contemporary or realistic problems, the use of cases in the classroom makes subject matter more relevant.

How can CBLbe used in the classroom?

• Case-based studies can be used in small or large classes.
• Cases can be used as the catalyst for class discussions and lectures.
• A student-centered discussion can be a main classroom activity as students collaborate to analyze the full dilemma and the data provided and decide upon a course of action.

Some common attributes of CBL

• Students define the nature of the problem as they perceive it, dividing a complex dilemma into manageable issues.
• Students bring their own background knowledge and principles to bear upon the case.
• Students raise points and questions, and defend their positions.
• Students formulate strategies to analyze the data and generate possible solutions.
• Collaboration and cooperation are key; competition is minimized.
• The instructor directs the student discussion but is not an authoritarian.
• Students may not agree, and sometimes a compromise is reached.

Eleven basic rules for CBL

Clyde Freeman Herreid provides eleven basic rules for CBL.

1. Tells a story.
   • It must have an interesting plot that relates to the experiences of the audience.
   • It must have a beginning, a middle, and an end.
   • The end may not exist yet; it will be what the students need to supply once the case is discussed.
2. Focuses on an interest-arousing issue.
3. Set in the past five years
   • To appear real the story must have the trappings of a current problem. This is not to denigrate classical or historical cases, but unless a case deals with current issues and the student feels the problem is important, some of its power is lost. If a student has just seen the problem mentioned in the media, so much the better. Thus, a case on human cloning will awaken the students' interest before one on the Copernican revolution. Even a case on cold fusion is old news today and lacks the luster it did in the chaotic days of the original report.
4. Creates empathy with the central characters.
   • We should create empathy not only to make the story line more engaging but because the personal attributes of the characters will influence the way a decision might be made. Certain decisions are beyond the scope of the characters' personalities and powers. It may be unrealistic for us to expect President Clinton to declare human cloning illegal all over the world by fiat, or for him not to comment about the NASA "Life on Mars" episode.
5. Includes quotations.
   • There is no better way to understand a situation and to gain empathy for the characters than to hear them speak in their own voices. Quotations add life and drama to any case. Quotations from documents and letters should be used as well. Quotations provide realism.
6. Relevant to the reader.
   • Cases should be chosen that involve situations that the students know or are likely to face. This improves the empathy factor and makes the case clearly something worth studying. Thus, for a graduate student in science, a case involving people arguing about authorship of a paper is of greater interest than sand flies in Uganda.
7. Must have pedagogic utility.
   • What function will the case serve? What does it do for the course and the student? What is the point of the story in the education of the student and is there a better way to do it?
8. Conflict provoking.
   • Robyn argues, "Most cases are fundamentally about something controversial," if not, what is there to talk about? She goes on, "Is this an issue about which reasonable people could disagree?" If so, you have the beginning of a good case.
9. Decision forcing.
   • Not all cases have to be dilemmas that need to be solved, but there is an urgency and a seriousness that is involved with such cases. We can easily second guess the owners of the shipping lines about the Valdez oil spill in retrospect, but at the time many of their decisions may have seemed quite reasonable. In dilemma or decision cases, students can not duck the issue, they must face problems head on. Without a dilemma in the case, a student can sit back and tsk tsk the way that a case unfolded. When they are forced to take a position, they are thrust into the action of the case.
10. Has generality.
    • What good is a case that is so specific that one can use it only as a curiosity? Cases must be of more use than a minor or local problem; they must have general applicability. If one writes a case about the cold fusion affair, there must be more to it than to state that Pons and Fleischmann made a mistake or that particular chemical reactions are not going to solve the world's energy problems.
11. Is short.
    • Cases must be long enough to introduce the facts of the case but not so long as to bore the reader or to make the analysis tedious. If one must introduce complexity, let it be done in stages. First, give some data and then a series of questions and perhaps a decision point before more information is introduced.

Type of Cases

The format of a case often influences how you choose to use it with students. Examples of cases with commonly encountered formats are provided with a brief description and likely implementation strategies.

1. Extensive, detailed case study.
   • Frequently used in business courses,
   • Often center on a particular decision, the people who made it, the people affected by it, and the impact of that decision on all parties.
   • May run 100 pages or more. Usually the student reads the entire case individually and prepares an analysis of the decisions with recommendations for change. The case is then discussed.
2. Descriptive, narrative cases, parts of which are given successively
   • Up to 5 pages
   • 1-2 paragraphs per page
   • Designed to be used over the course of two or more class meetings.
   • Disclosed to the students one page at a time, with discussion, hypothesis generation and development of learning goals and study questions for each part of the case.
   • Objectives are given to the student toward the end of the case.
   • This style of case originated in medical settings.
3. MiniCases
   • designed to be used in a single class meeting,
   • usually tightly focused.
   • useful for helping students apply concepts, for introducing practical applications in lab settings, or as a pre-lab exercise designed to make lab work more meaningful.
4. Bullet Cases
   • Two or three sentences with a single teaching point.
   • Similar to problems commonly used on exams, however, students discuss them in small groups.
5. Directed Case Study
   • Short cases are followed immediately with highly directed questions.
6. Fixed Choice Options (Multiple Choice Cases)
   • May be a variation on bullet cases above,
   • Is a minicase with 4-5 plausible solutions. In groups students must choose and defend one solution.
   • Useful for policy, ethics, design decisions.
   • Good for short, in-class uses.
   • Multiple choice questions might convert easily to these.

Learning Goals and Course Objectives

• Which goals could be met by having students use the casestudy approach? Often a case will allow students to address more than one goal at a time. This kind of analysis can be a starting place for case writing.
• A second way to use the goals of the course is when you evaluate a case for use in your class. Ask yourself these questions:
  • What is the case about?
  • What are some of the potential learning issues?
  • Are these central enough to the case for me to use this case?
  • Can I modify the case?
  • How difficult or obscure are the issues in the case?
  • Will there be issues my students will care about?
  • Is the case open-ended enough for students to go beyond fact finding?
  • What do I see as possible areas for investigation?
  • What product might I ask students to produce?
  • Is the case too short or too long for the time I have available?
  • What sorts of learning resources might be needed for this case? Are they accessible?
  • If I use this case, what lectures/labs/discussions might I want to change, add or eliminate?

Course Structure

As you can see from the above list of questions, sometimes using cases can lead to changing a course syllabus, to delete, rearrange, change or add other components like lectures or labs.

Another consideration is the temporal structure of the course, and the space available for teaching. When does the course meet? How often? How long? For what purposes? When would you fit in cases? Some suggested "prototypical weeks". Traditional 3 hours of lecture, 2-3 hours in lab Option A Two blocks per week "workshop" style with some time for case work Option B Combine lecture and case work, sandwiching lab Option C Start case on Fri., work on in lab, finish next Fri. Other options Create your own

Class Size

Classes come in all sizes. Implementing CBL in different sized classes requires planning.

In very large classes:

• cases could be short introductory experiences that lead into additional learning experiences in lab or recitation time.
• Some part of the lecture time is used to provide the case background, perhaps in a short video segment.
• Directed cases with a defined problem space are used within large lecture settings by selecting class members to respond individually.
• Often individuals are chosen to report on the progress of short periods of work accomplished within proximity groups of students.
• There are many solutions to having students in larger classes do meaningful work in smaller groups. Additional support for case based teaching can be provided by faculty working in teams, graduate students (if available) and advanced undergraduate teaching assistants.
• It is possible to break up large classes into smaller groups, but you do need a high tolerance for noise while a couple of hundred students, working in near-neighbor groups, discusses a case.
• Peer interactions are enriched by the prior knowledge, experience and interests the larger number of students bring to the process.

In smaller classes:

• real advantage for students learning how to work together on cases.
• Groups can be smaller and more easily interacted with.
• Investigative CBL works well in this setting.
• Further research options might include modeling and simulation, data mining, or data visualization.

In virtual classes:

• cases are introduced electronically with student groups working together on-line.
• also works well to extend opportunities for community college students who may be older and working. There are faculty whose case materials and advice are made available on line.

Preparing students to use case study approaches

Most college students are ill-prepared for collaborative group work. Nonetheless, at present, college faculty need to recognize that they will have to teach students how to work together. They will also have to teach them how to use case study approaches.

Address student concerns by providing access to specific information on what to expect with CBL such as: Notes for Students on Investigative CBL At Harvard Medical School, incoming classes of medical students are introduced to CBL in 3 ways.

1. in orientation, they do a case about plumbing (which few know about and it isn't medical, so the pressure is off).
2. also during orientation, they sit as a group of 160 in a lecture hall and watch a small group tutorial take place live in front of them (run by second year students).
3. in their first real course, time is allotted for discussing group dynamics and case processes.

You will likely want to make a low-pressure situation for your students the first time they do a case. Make it small, fun and easy, so they can learn how to brainstorm the issues and questions of the case. Don't be afraid to give explicit directions, such as:

• "We begin by having one person read the case out loud. Who would like to do this?"
• "Are there any words you don't know?" Or "what do you think this case is about?"
• "It will help you later if one ofyou acts as scribe and writes down the ideas (on the chalkboard). You might want to keep track of facts, questions, issues, and proposed answers to the problem."
• "We have 10 minutes left and you need to plan for next meeting. What do you see as key issues you'd like to work on?"

Students also need guidelines for how to act during discussions. Having printed guidelines can help, such as

• "Don't interrupt one another" ... "Don't attack people personally, focus on ideas"... "Each person must contribute to the group. There are many ways to do this."

See also: cognitive flexibility theory

References

• http://ublib.buffalo.edu/libraries/projects/cases/teaching/good-case.html

• http://www.queensu.ca/ctl/goodpractice/case/index.html

• http://www.pitt.edu/~ciddeweb/faculty-development/FDS/casebase.html

• http://www.bioquest.org/usernote.html

• Jonassen, David H. & Julian Hernandez-Serrano, Case-Based Reasoning and Instructional Design: Using Stories to Support Problem Solving ETR&D, Vol. 50, No. 2, 2002, pp. 65-77 ISSN 1042-1629.

• Lundeberg, M., B. Levin and L. Harrington (2000). Who Learns What from Cases and How ? : The Research Base for Teaching and Learning With Cases, Mahwah, NJ, Lawrence Erlbaum Associates.

• Williams, S. M., (1992) Putting Case-Based Instruction Into Context: Examples From Legal and Medical Education. Journal of the Learning Sciences, 2, 367- 427.