Case-based learning: Difference between revisions
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** a business cases may require over a year of information gathering and interviews along with thousands of dollars of investment to develop a case that may extend over several class sessions. | ** a business cases may require over a year of information gathering and interviews along with thousands of dollars of investment to develop a case that may extend over several class sessions. | ||
;Pre-existing Materials | |||
* can be found prepackaged almost anywhere (newspapers, magazines, novels, cartoons, videos, and television dramas). For example, the movie "Jurassic Park" is an ideal story to consider questions about scientific responsibility as well as DNA technology. | * can be found prepackaged almost anywhere (newspapers, magazines, novels, cartoons, videos, and television dramas). For example, the movie "Jurassic Park" is an ideal story to consider questions about scientific responsibility as well as DNA technology. | ||
* Another technique is to simply collect a series of articles focused around a single topic. If accompanied by a short series of questions to guide student's reading, an outstanding case can be developed. | * Another technique is to simply collect a series of articles focused around a single topic. If accompanied by a short series of questions to guide student's reading, an outstanding case can be developed. | ||
* In summary, pre-existing materials are cheap and easy to find. They come from familiar sources and are recognizable as authentic parts of the student's world. There is an immediacy in their use; one can see an article in the press in the evening and be using it in the classroom the next day. | * In summary, pre-existing materials are cheap and easy to find. They come from familiar sources and are recognizable as authentic parts of the student's world. There is an immediacy in their use; one can see an article in the press in the evening and be using it in the classroom the next day. | ||
;Writing Cases | |||
* Many cases are best developed from scratch (most business cases and although it requires considerable time, it has the advantage that only essential material is included in the writing). | * Many cases are best developed from scratch (most business cases and although it requires considerable time, it has the advantage that only essential material is included in the writing). | ||
* May be customized exactly to meet the teacher's goals. | * May be customized exactly to meet the teacher's goals. |
Revision as of 16:13, 16 August 2006
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 Intelligent tutoring systems, 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.
- 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.
- Focuses on an interest-arousing issue.
- Set in the past five years (increase the motivation of the students)
- Creates empathy with the central characters.
- to make the story line more engaging
- because the personal attributes of the characters will influence the way a decision might be made.
- Includes quotations.
- add life and drama to any case.
- provide realism.
- Relevant to the reader.
- This improves the empathy factor and makes the case clearly something worth studying.
- Must have pedagogic utility.
- Conflict provoking.
- Decision forcing.
- In dilemma or decision cases, students can not duck the issue, they must face problems head on.
- Has generality.
- Cases must be of more use than a minor or local problem; they must have general applicability.
- Is short.
- 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.
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.
- 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.
- 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.
- 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.
- 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.
- Directed Case Study
- Short cases are followed immediately with highly directed questions.
- 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.
- in orientation, they do a case about plumbing (which few know about and it isn't medical, so the pressure is off).
- 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).
- 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."
How to write a case
- work required in writing the case varies enormously depending upon the materials you decide to provide the students. You can use for example:
- a 100-word paragraph from a journal
- an elaborate preparation requiring dozens of pages of text and extensive research.
- a business cases may require over a year of information gathering and interviews along with thousands of dollars of investment to develop a case that may extend over several class sessions.
- Pre-existing Materials
- can be found prepackaged almost anywhere (newspapers, magazines, novels, cartoons, videos, and television dramas). For example, the movie "Jurassic Park" is an ideal story to consider questions about scientific responsibility as well as DNA technology.
- Another technique is to simply collect a series of articles focused around a single topic. If accompanied by a short series of questions to guide student's reading, an outstanding case can be developed.
- In summary, pre-existing materials are cheap and easy to find. They come from familiar sources and are recognizable as authentic parts of the student's world. There is an immediacy in their use; one can see an article in the press in the evening and be using it in the classroom the next day.
- Writing Cases
- Many cases are best developed from scratch (most business cases and although it requires considerable time, it has the advantage that only essential material is included in the writing).
- May be customized exactly to meet the teacher's goals.
- Reynolds (1980) has classified cases into three basic types:
- Decision or dilemma cases present problems or decisions that need to be made by a central character in a drama.
- usually consists of a short introductory paragraph setting up the problem to be considered and may introduce the decision-maker at the moment of crisis.
- A background section fills in the historical information necessary to understand the situation.
- A narrative section then presents the recent developments leading up to the crisis that our protagonist faces.
- Appendices follow including tables, graphs, letters, or documents that help lay the foundation for a possible solution to the problem.
- Appraisal cases ("issue cases") are used to teach students the skills of analysis. #* The material is focused around answering questions like "What is going on here?"
- This type of case frequently lacks a central character in the drama and generally stops short of demanding that the students make a decision.
- Case histories are largely finished stories
- generally less exciting than decision or appraisal cases.
- can serve as illustrative models of science in action and they provide plenty of opportunities for Monday-morning quarterbacking.
- Science is replete with cases of this type (e.g. the Copernican revolution, cold fusion, ...)
- Decision or dilemma cases present problems or decisions that need to be made by a central character in a drama.
How to teach a case
In almost all methods there is a common approach. The instructor must have his objectives clearly in mind, must structure the presentation to develop the analytical skills of the students, and must be sure that student participation is maximized.
Discussion Format
- classically used by business and law schools to deal with cases.
- Students are usually presented with decision or appraisal cases.
- The instructor's job is to identify, with the student's help, the various issues and problems, possible solutions, and consequences of action.
- simple method : the instructor asks probing questions and the students analyze the problem depicted in the story with clarity and brilliance.
Case discussion instructors vary enormously in their classroom manner:
- strong intimidating approach.
- The "all-knowing" instructor (acting as inquisitor, judge, and jury) tries to extract wisdom from his student victim.
- In its worst form, the questioning can be a version of "I've got a secret, and you have to guess it."
- In its best form, it can bring about an intellectual awakening as insights emerge from a complex case.
- almost nondirective class discussion.
- The instructor can practically stay on the sidelines while the students take over the analysis.
- The instructor may start the discussion with a minimum of fuss saying, "Well, what do you think about the case?"
- From that moment on, the instructor may merely act as a facilitator, being sure that some semblance of order is kept and students get to voice their views.
- Finally, the class may end without any resolution of the issue or summation.
Most practitioners of the discussion method prefer a middle ground. William Welty (1989) argues for such an approach with proper introduction, directive but not dominating questioning, good blackboard work to highlight the essential issues, and an appropriate summary.
Debate Format
- well suited for many types of cases where two diametrically opposed views are evident.
Public Hearing Format
- ideal format to allow a variety of people to speak and different views to be expressed.
- Their use in case studies has similar strengths and has the added virtue of mimicking real-world events.
- Public hearings are structured so that a student panel, role-playing as a hearing board, listens to presentations by different student groups.
Trial Format
- have inherent fascination because of their tension and drama.
- two opposing sides each represented by an attorney, with witnesses and cross-examination.
Problem Based Learning Format
- Medical schools have used the case method of instruction for years.
- PBL is faculty-intensive, for it uses one tutor for every four or five students. They stay together for the entire term, working through a series of cases.
- The cases are typically linked by some common area of study or progressive shift in complexity.
A typical case passes through several stages. In their first meeting, the instructor presents a short written account of the patient with some symptoms and background. The faculty and students together try to identify the points they think they understand and determine those terms, tests, procedures, symptoms, etc., for which they need more information. At the end of this meeting, students agree on how each will divide up the responsibilities to search for the needed information in the libraries.
In the second meeting, students discuss their findings and share opinions. Their search for the correct diagnosis narrows down. By the end of the class meeting, the students have determined what new information they need to uncover and go their separate ways to find it.
At the third meeting, students share their thoughts, data, and understanding. They try to reach closure on the diagnosis and treatment. This is the last step in the process and generally students will not find out the "real" answer to the problem. The knowledge and understanding of the case comes from the search for answers, not from "the answer" to a particular case. The power of this method is its interactive approach between thinking, discussion, and searching for more information. Consequently, it mimics the approach we usually use in real life.
Scientific Research Team Format
- The essence of most scientific research is the case method.
- scientists are constantly confronted by problems, questions, or dilemmas
- they usually have a large background of information, which they can use to "solve the problem."
they use some version of the hypothetico-deductive method where we ask questions, make hypotheses, make predictions, test predictions by observation and experiment as they collect data, compare the results with their predictions, and make evaluations and draw conclusions.
Here is an example of student-research projects which involves the simple collecting of rain samples in different regions of the campus or city and measuring pH. The data collected over a semester will yield lots of tables and graphs for comparison with other regions of the country and lead to discussions of acid rain and its effect upon the ecosystem. Mundane though this project seems it instills in students a great sense of many steps in the collection and analysis of data.
See also: cognitive flexibility theory
References
- 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.
- Reynolds, J.I. 1980. Case types and purposes. In Reynolds, R.I., Case Method in Management Development: Guide for Effective Use. Geneva, Switzerland: Management Development Series No. 17, International Labour Office (Chap. 9).
- Welty, William M. 1989. Discussion method teaching. Change July/Aug:41-49.
- Williams, S. M., (1992) Putting Case-Based Instruction Into Context: Examples From Legal and Medical Education. Journal of the Learning Sciences, 2, 367- 427.