How to... undertake case study research
By Margaret Adolphus
What is case study research?
Case study research, in which the subject of the research is studied within its social, political, organizational, or economic context, is one of the commonest approaches across the social and management sciences.
Many authors cite Yin, who describes case study research as:
" ... an empirical inquiry that investigates a contemporary phenomenon in depth and within its real-life context, especially when the boundaries between phenomenon and context are not clearly evident" (Yin, 2009, location no. 638-650).
In other words, the subject of the research is comprehensively studied as an example of a real live phenomenon, within the context in which it happens.
Another definition is given by Dul and Hak:
"A case study is a study in which a) one case (single case study) or a small number of cases (comparative case study) in their real life context are selected, and b) scores obtained from these cases are analysed in a qualitative manner" (Dul and Hak, 2007, p. 4).
How and when is the case study method used?
According to Yin (2006), case study research is best applied when the research addresses descriptive or explanatory questions: i.e. what happened, how, and why?
It is also good for describing a situation or phenomenon occurring in the present, where in-depth description is useful and where the researcher does not need to manipulate events.
Yin (2003) identifies three types of case studies:
- Exploratory: the case study is used to define questions and hypotheses – or to test out a research procedure – for a further piece of research, such as a large-scale survey.
- Descriptive: the case study is used to describe a particular phenomenon within its context. It can be used to expand on a particular theme unearthed by a survey.
- Explanatory: the case study explores cause-effect relationships, and/or how events happen.
Only the third of these approaches can stand up as a method in its own right, and not as an ancillary to other quantitative approaches such as surveys or field experiments.
Advantages of the case study as a research method
Case studies are "real" – they offer a chance to get a snapshot of real life: a rich and thick picture. As such, they are most appropriate for dealing with a subject that is context dependent, complex, unusual, or where there is some ambiguity.
In direct contrast to positivist approaches, which seek to generalize, the case study offers particularity: i.e. the opportunity for a holistic approach without the distraction of too many variables (Gummesson, 2007).
While it offers depth and specificity, case study research also offers breadth and diversity in terms of methods of data collection and analytical techniques. For example, one case study can incorporate surveys, interviews, direct observation, and archival research. This offers the possibility of several different layers of analysis which can reveal several different perspectives, with the added benefit of triangulation of the results.
According to Woodside (2010, pp. 2-3) the usefulness of case study research lies in the fact that it encourages research methods that help measure thinking over an ongoing period, for example by multiple interviews.
It can also be a useful method when the unit of analysis, or the subject under consideration, is a collective entity such as an organization or a community.
Disadvantages of the case study as a research method
The most common objection to case study research is that it is insufficiently rigorous. Quite often this criticism relates not to the method as such, but to the way case studies are presented: the author does not leave a clear audit trail detailing his or her research and explaining the conclusions.
Case studies are often seen as a "bolt-on" to a major research project, defining research questions or throwing further light on an issue that has been revealed by a survey. That explanatory research can offer an understanding of a phenomenon is viewed with scepticism by some, on the grounds that a single case study cannot yield a sufficient volume of evidence on which to generalize.
What are the skills needed in case study research?
Case study research is neither a quick nor a soft option. It requires considerable skill on the part of the researcher, who needs to be adept at identifying and analysing data from a number of different sources.
It also requires a skill common to all qualitative researchers: the ability to interpret as well as analyse, to see through spin, and if necessary, check information with another source.
In the social sciences and life sciences, a case study is a research method involving an up-close, in-depth, and detailed examination of a subject of study (the case), as well as its related contextual conditions.
Case studies can be produced by following a formal research method. These case studies are likely to appear in formal research venues, as journals and professional conferences, rather than popular works. The resulting body of 'case study research' has long had a prominent place in many disciplines and professions, ranging from psychology, anthropology, sociology, and political science to education, clinical science, social work, and administrative science.
In doing case study research, the "case" being studied may be an individual, organization, event, or action, existing in a specific time and place. For instance, clinical science has produced both well-known case studies of individuals and also case studies of clinical practices. However, when "case" is used in an abstract sense, as in a claim, a proposition, or an argument, such a case can be the subject of many research methods, not just case study research. Case studies may involve both qualitative and quantitative research methods.
Another suggestion is that case study should be defined as a research strategy, an empirical inquiry that investigates a phenomenon within its real-life context. Case study research can mean single and multiple case studies, can include quantitative evidence, relies on multiple sources of evidence, and benefits from the prior development of theoretical propositions. Case studies should not be confused with qualitative research and they can be based on any mix of quantitative and qualitative evidence. Single-subject research provides the statistical framework for making inferences from quantitative case-study data. This is also supported and well-formulated in Lamnek, 2005[page needed]: "The case study is a research approach, situated between concrete data taking techniques and methodologic paradigms."[this quote needs a citation]
Case studies in research may be mistaken for the case method used in teaching.
Different types of case study research methods
Ridder (2017) (similarly also Welch et al., 2011) distinguishes four common case study approaches. First, there is the “no theory first” type of case study design, which is closely connected to Eisenhardt’s methodological work. The second type of research design is about “gaps and holes”, following Yin’s guidelines and making positivist assumptions. A third design deals with a “social construction of reality”, which is represented by Stake. Finally, the reason for case study research can also be to identify “anomalies”. A representative scholar of this approach is Burawoy. Each of these four approaches has its areas of application, but it is important to understand their unique ontological and epistomological assumptions. There are substantial methodological differences between these approaches.
Besides these research methods are very different in nature, "case study" can also refer to a teaching method.
Case selection and structure
An average, or typical case, is often not the richest in information. In clarifying lines of history and causation it is more useful to select subjects that offer an interesting, unusual or particularly revealing set of circumstances. A case selection that is based on representativeness will seldom be able to produce these kinds of insights. When selecting a case for a case study, researchers will therefore use information-oriented sampling, as opposed to random sampling.Outlier cases (that is, those which are extreme, deviant or atypical) reveal more information than the potentially representative case, as seen in the cases selected for more qualitative safety scientific analyses of accidents for example (see e.g. ). A case may be chosen because of the inherent interest of the case or the circumstances surrounding it. Alternatively it may be chosen because of a researchers' in-depth local knowledge; where researchers have this local knowledge they are in a position to "soak and poke" as Fenno puts it, and thereby to offer reasoned lines of explanation based on this rich knowledge of setting and circumstances.
Three types of cases may thus be distinguished for selection:
- Key cases
- Outlier cases
- Local knowledge cases
Whatever the frame of reference for the choice of the subject of the case study (key, outlier, local knowledge), there is a distinction to be made between the subject and the object of the case study. The subject is the “practical, historical unity” through which the theoretical focus of the study is being viewed. The object is that theoretical focus – the analytical frame. Thus, for example, if a researcher were interested in US resistance to communist expansion as a theoretical focus, then the Korean War might be taken to be the subject, the lens, the case study through which the theoretical focus, the object, could be viewed and explicated.
Beyond decisions about case selection and the subject and object of the study, decisions need to be made about purpose, approach and process in the case study. Thomas thus proposes a typology for the case study wherein purposes are first identified (evaluative or exploratory), then approaches are delineated (theory-testing, theory-building or illustrative), then processes are decided upon, with a principal choice being between whether the study is to be single or multiple, and choices also about whether the study is to be retrospective, snapshot or diachronic, and whether it is nested, parallel or sequential. It is thus possible to take many routes through this typology, with, for example, an exploratory, theory-building, multiple, nested study, or an evaluative, theory-testing, single, retrospective study. The typology thus offers many permutations for case-study structure.
A closely related study in medicine is the case report, which identifies a specific case as treated and/or examined by the authors as presented in a novel form. These are, to a differentiable degree, similar to the case study in that many contain reviews of the relevant literature of the topic discussed in the thorough examination of an array of cases published to fit the criterion of the report being presented. These case reports can be thought of as brief case studies with a principal discussion of the new, presented case at hand that presents a novel interest.
Some issues are usually realised in a situation where marketing is concerned. One must, therefore, ensure that he/she can fully understand these things. In a case where the market of any organisation is in a messy state, the agency will always seek to find out some of the reasons why the scenario is that way. They will have to gather information that may help them in solving such issues. For this to be fully achieved, one must be able to carry out a market research to establish where the problem is. This, therefore, calls for the different methods which can be used in a situation where one wants to conduct a marketing research. Some ways can be used to come up with the purpose of study that is most appropriate. The organisations have to choose one of the available techniques so that they can thoroughly conduct their investigations. Some of the primary methods that would be used included interviews, surveys, focus groups, observations and in some cases use field trials. These methods mainly depended on the amount of cash they organisation is willing to spend in having this market research done and also the kind of data that is required by the group.
In our case, the British Airways company is undergoing some series of complications. There have been some complaints from their client as about some issues. Apart from those, there have been some serious issues such as most of their members of staff engaging in the strike as they demand their payments. There have also been significant delays in some of the secured flights just because of the problems associated with their computers. This has mainly sparked most of their clients who have, as a result, felt angered. Most of their brands have also been damaged.
The best method
In such a scenario, it is usually significant that we research so that we can know what the problem is. This can only be achieved through means that will enable us to find the suitable information that will help in preparation of the action plan to solve these issues. The best method to be used here is that of surveys. The organisation should be able to apply this way because they will be able to get sufficient information which pertains to their brand image from most of their clients. Most of the customers will also complete the survey by ensuring that they give reasons for their various attitudes towards the company’s brand.
Advantages of surveys
One of the benefits of this method is that the company will be able to get feedback from a significant portion of customers. Most of the customers will be able to answer the questions which will pertain to the brand and therefore a concrete feedback will be achieved. The other merit is the fact that it is less costly when compared to the others such as interviews. The company will just have to pay for the production of questionnaires used in the survey.
Limitation of the method
On the other hand, surveys also have demerits. One of the disadvantages is the fact that their design is inflexible. This is because the study that the company uses from the beginning, as well as its administration, cannot be changed throughout the process of gathering data that is meaningful. In some cases, the survey questions are usually inappropriate since the company will be forced to come up with items that will be used by the entire body of customers.
Types of case studies
In public-relations research, three types of case studies are used:
Under the more generalized category of case study exist several subdivisions, each of which is custom selected for use depending upon the goals of the investigator. These types of case study include the following:
- Illustrative case studies. These are primarily descriptive studies. They typically utilize one or two instances of an event to show the existing situation. Illustrative case studies serve primarily to make the unfamiliar familiar and to give readers a common language about the topic in question.
- Exploratory (or pilot) case studies. These are condensed case studies performed before implementing a large scale investigation. Their basic function is to help identify questions and select types of measurement prior to the main investigation. The primary pitfall of this type of study is that initial findings may seem convincing enough to be released prematurely as conclusions.
- Cumulative case studies. These serve to aggregate information from several sites collected at different times. The idea behind these studies is that the collection of past studies will allow for greater generalization without additional cost or time being expended on new, possibly repetitive studies.
- Critical instance case studies. These examine one or more sites either for the purpose of examining a situation of unique interest with little to no interest in generalization, or to call into question a highly generalized or universal assertion. This method is useful for answering cause and effect questions.
Case Studies in Business
At Harvard Law School In 1870, Christopher Langdell departed from the traditional lecture-and-notes approach to teaching contract law and began using cases pled before courts as the basis for class discussions. By 1920, this practice had become the dominant pedagogical approach used by law schools in the United States; it also was adopted by Harvard Business School.
Research in business disciplines is usually based on a positivistepistemology, namely, that reality is something that is objective and can be discovered and understood by a scientific examination of empirical evidence. But organizational behavior cannot always be easily reduced to simple tests that prove something to be true or false. Reality may be an objective thing, but it is understood and interpreted by people who, in turn, act upon it, and so critical realism, which addresses the connection between the natural and social worlds, is a useful basis for analyzing the environment of and events within an organization.
Case studies in management are generally used to interpret strategies or relationships, to develop sets of “best practices”, or to analyze the external influences or the internal interactions of a firm. With several notable exceptions (e.g., Janis on Groupthink), they are rarely used to propose new theories.
Generalizing from case studies
A critical case is defined as having strategic importance in relation to the general problem. A critical case allows the following type of generalization: "If it is valid for this case, it is valid for all (or many) cases." In its negative form, the generalization would run: "If it is not valid for this case, then it is not valid for any (or valid for only few) cases."
The case study is effective for generalizing using the type of test that Karl Popper called falsification, which forms part of critical reflexivity. Falsification offers one of the most rigorous tests to which a scientific proposition can be subjected: if just one observation does not fit with the proposition it is considered not valid generally and must therefore be either revised or rejected. Popper himself used the now famous example: "All swans are white", and proposed that just one observation of a single black swan would falsify this proposition and in this way have general significance and stimulate further investigations and theory-building. The case study is well suited for identifying "black swans" because of its in-depth approach: what appears to be "white" often turns out on closer examination to be "black".
Galileo Galilei built his rejection of Aristotle's law of gravity on a case study selected by information-oriented sampling and not by random sampling. The rejection consisted primarily of a conceptual experiment and later on a practical one. These experiments, with the benefit of hindsight, seem self-evident. Nevertheless, Aristotle's incorrect view of gravity had dominated scientific inquiry for nearly two thousand years before it was falsified. In his experimental thinking, Galileo reasoned as follows: if two objects with the same weight are released from the same height at the same time, they will hit the ground simultaneously, having fallen at the same speed. If the two objects are then stuck together into one, this object will have double the weight and will according to the Aristotelian view therefore fall faster than the two individual objects. This conclusion seemed contradictory to Galileo. The only way to avoid the contradiction was to eliminate weight as a determinant factor for acceleration in free fall. Galileo’s experimentalism did not involve a large random sample of trials of objects falling from a wide range of randomly selected heights under varying wind conditions, and so on. Rather, it was a matter of a single experiment, that is, a case study.
Galileo’s view continued to be subjected to doubt, however, and the Aristotelian view was not finally rejected until half a century later, with the invention of the air pump. The air pump made it possible to conduct the ultimate experiment, known by every pupil, whereby a coin or a piece of lead inside a vacuum tube falls with the same speed as a feather. After this experiment, Aristotle’s view could be maintained no longer. What is especially worth noting, however, is that the matter was settled by an individual case due to the clever choice of the extremes of metal and feather. One might call it a critical case, for if Galileo’s thesis held for these materials, it could be expected to be valid for all or a large range of materials. Random and large samples were at no time part of the picture. However it was Galileo's view that was the subject of doubt as it was not reasonable enough to be the Aristotelian view. By selecting cases strategically in this manner one may arrive at case studies that allow generalization.
It is generally believed[by whom?] that Frederic Le Play first introduced the case-study method into social science in 1829 as a handmaiden to statistics in his studies of family budgets.
Other roots stem from the early 20th century, when researchers working in the disciplines of sociology, psychology, and anthropology began making case studies. In all these disciplines, case studies were an occasion for postulating new theories, as in the grounded-theory work of sociologists Barney Glaser (1930- ) and Anselm Strauss (1916-1996).
The popularity of case studies in testing theories or hypotheses has developed only in recent decades. One of the areas in which case studies have been gaining popularity is education and in particular educational evaluation.
Educators have used case studies as a teaching method and as part of professional development, especially in business and legal education. The problem-based learning (PBL) movement offers an example. When used in (non-business) education and professional development, case studies are often referred to as critical incidents.
Ethnography exemplifies a type of case study, commonly found in communication case studies. Ethnography is the description, interpretation, and analysis of a culture or social group, through field research in the natural environment of the group being studied. The main method of ethnographic research is thorough observation, where the researcher observes study participants over an extended period of time within the participants' own environment.
Comparative case studies have become more popular[when?] in social science, policy, and education research. One approach encourages researchers to compare horizontally, vertically, and temporally.
Using case studies in research differs from their use in teaching, where they are commonly called case methods and casebook methods. Teaching case studies have been a highly popular pedagogical format in many fields ranging from business education to science education. Harvard Business School has been among the most prominent developers and users of teaching case studies. Business school faculty generally develop case studies with particular learning objectives in mind. Additional relevant documentation, such as financial statements, time-lines, and short biographies, often referred to in the case study as exhibits, and multimedia supplements (such as video-recordings of interviews with the case subject) often accompany the case studies. Similarly, teaching case studies have become increasingly popular in science education. The National Center for Case Studies in Teaching Science has made a growing body of case studies available for classroom use, for university as well as secondary school coursework. Nevertheless, the principles involved in doing case study research contrast with those involved in doing case studies for teaching. Teaching case studies need not adhere strictly to the use of evidence, as they can be manipulated to satisfy educational needs. The generalizations from teaching case studies also may relate to pedagogical issues rather than the substance of the case being studied.
Case studies are commonly used in case competitions and in job interviews for consulting firms such as McKinsey & Company, CEB Inc. and the Boston Consulting Group, in which candidates are asked to develop the best solution for a case in an allotted time frame.
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