[ RESEARCH FOR mE CLINICIAN J

Case Reports and Case Studies: A Discussion of Theory and Methodology in Pocket Format

I n this time of managed care one may feel like a

lone ship in a sea of change. However, the individual can still have great impact. John Glenn sent a message that is changing the beliefs and expectations about activity levels of older in­dividuals. The case report pre­sented on the Internet about the allotransplantation of a hand changes expectations for patients with amputations and raises eth­ical dilemmas associated with new technology.

Case reports are an estab­lished scientific method in the be­havioral and medical sciences. In 1817, James Parkinsonl presented a series of case reports to illus­trate his neurological explana­tions about "shaking palsy." Some researchers have consid­ered case studies a weak sibling among scientific methods. How­ever, when performed with rigor, the case study can provide in­depth information that cannot be obtained from group studies.2

The purpose of this paper is to review some pertinent issues in the application of case reports and case studies. It is important to know the opportunities and limitations of this type of inves­tigation. The premise is that a disciplined inquiry of a case will improve the quality and clarity of the case report and, thereby en­hance understanding among therapists. The American Journal of Occupational Therapy and the journal Physical Therapy both con­sider reports and research studies of single subjects important con­tributions to their body of knowl­edge. The Journal of Hand Therapy has published case reports and case studies as well. However, a

consensus among hand thera­pists regarding how these tech­niques can be applied to hand therapy is still lacking. This pa­per may serve as a starting point to establish some specific guide­lines for clinical applications.

Definitions

The terms "case studies," "case study designs," and "case reports" are sometimes used in­terchangeably, but differences be­tween them have implications for the method by which an inquiry is performed, the way results are reported, and how conclusions are drawn. In a guide to writing case reports, McEwen3 delineates

All measurements and interventions are documented so that the reader can visualize exactly what was done.

the boundaries as follows: Case reports are descriptions of prac­tice without the application of re­search methodology. The objec­tive of a case report is to describe practice, not to determine cause and effect of practice. Case studies utilize standards of scientific methods. A case study is an em­pirical inquiry that investigates a contemporary phenomenon in its real-life context, especially when the boundaries between the phe­nomenon and the context are not clearly evident.4 The case can be

230 JOURNAL OF HAND THERAPY

a person, a group of persons, a unit, or a group of multiple units. The term "single-subject design" is reserved for those case studies that involve the implementation of an experimental design in a controlled manner. Implications of this nomenclature will be clar­ified later in the description of re­search methods.

Classifications

The type of case inquiry can be classified according to the type of research question to be answered. The question can range from "what" to "why" and "how. ,,4 A classification that opens up the awareness of op­portunities for case studies is based on the differences between a descriptive case study, an ex­planatory case study, and an ex­ploratory case study. "What" questions pertain to the results of a treatment or to what compo­nents of a treatment made a cru­cial difference. As such, the de­scriptive case study and the exploratory case study can coin­cide. Questions asking "why" and "how" a treatment makes a difference qualify as explanatory.

Format

The format of the report of a case inquiry follows that of an ex­perimental research report, with some modifications. A case study or report contains the following headings: Introduction, Methods, Results, Discussion, and Conclu­sions. The introduction contains the research question and a re­view of the literature to justify the need for the study. The intro­duction leads to a solid statement

of the purpose of the study. The methods section describes the study design, the case, and the implemented treatment, if appro­priate. It also contains the out­come measures used. The results section describes the outcomes. The results can be presented with the description of the interven­tion or in a separate section. Thus, a difference in format can exist between a research report and a case report, because in a re­search report methods and study results are always presented in separate sections with separate headings. In the discussion sec­tion, the authors place the results in the context of the literature and the guiding question of the inquiry. The conclusion provides the closure of the project and the "take-home" message.

Methology

Design. The research de­sign is the logic that links the collected data to the research question and the conclusions.4

Designs of case inquiries can be performed retrospectively, simul­taneously, or prospectively. Case reports aim to describe results of practice. The research question of the case report is not posed to ad­dress a cause and effect. There­fore, the methodology does not comply with cause-and-effect de­signs, such as random assign­ment to different treatment pro­tocols. Case studies involve controlled experimentation and therefore implement design for­mats. Well-known formats are the A-B and A-B-A designs, in which a period of baseline mea­surements (A) precedes a period of experimental intervention (B), possibly followed by another pe­riod of monitoring (A).5,6

Description of the Case. A case is defined as a single entity. A patient may be a case, but so may a department, a system of health care delivery, a city, or a country for that matter. McEwen3

states that the importance of the case is not limited to a single pa­rameter representing the case, but includes a broad description of the conditions and the context of the entity under investigation.

Because the boundaries between the case and the real-life context are not always known, the case needs to be described compre­hensively, in detail. Therefore, the inquiry may contain multiple sources of information and evi­dence.

Description of the Interven­tion. Any intervention needs to be described in detail. Practice of­ten involves the application of several treatments, and all com­ponents need to be described. Meticulous attention to detail is the hallmark of the well-written case report or study. All measure­ments and treatment interven­tions are documented as to when and how much, so that the reader can visualize exactly what was done in the case. For example, Nakada and Uchida/ in describ­ing a general program of sensory education, report how the pro­gram was adjusted to a unique case and what the results of the intervention were. The authors describe what the focus of the treatment was, based on the goals of the patient and func­tionallimitations observed by the investigator. The specifics of the

A limitation of the case study is that results cannot be generalized to the population at large.

treatment-i.e., the mode of in­tervention-are described in de­tail. The authors should have described more clearly the fre­quency and duration of imple­mented interventions, to allow replication with similar patients.

Outcome Measures. The types of documentation included in a case study or report can range from pictures and diaries to commonly used standardized measurement tools. Measures de­signed to evaluate all levels of disability (according to the defi­nitions by the World Health Or­ganization) should be used for a

comprehensive description of the patient and the context. Not only measures of impairment but also measures of functional limitation or disabilitl should be used, be­cause a change in the level of im­pairment does not automatically translate to a change in func­tional ability or in disability. It is important that the selected out­come measures be valid for de­scribing the phenomenon and sensitive to changes in the con­dition of the case. Reliability of the selected measures is just as important for a case inquiry as for other scientific inquiries, and should be included in the report. If a measure is not reliable, the outcomes will vary because of in­consistency and will thus obscure changes due to the applied inter­vention. That does not mean that experimental measures cannot be used to enrich the body of stan­dardized measures.

Description and Analysis of the Results. Results are de­scribed in written text, graphic format, or in tables. Outcomes can be described concurrently with the intervention or collec­tively after the intervention. The data analysis depends on the re­search question and design. The data analysis can consist of a vi­sual inspection of the data. The use of statistical analyses to ana­lyze case study reports is de­bated, because many statistical techniques are based on the fact that a sample is randomly drawn from a population at large. How­ever, various techniques of statis­tical data analysis of single-case experimental designs exist, such as the split-middle trend line, the running medians procedure, and time-series analysis.5,6,8

Discussion and Conclu­sion. In the discussion the au­thors reflect on the findings of the case and place the results of the case in the context of the litera­ture. It is important to remember the focus of the research ques­tion. Usually the question is not a cause-and-effect question and, therefore, causal conclusions should not be drawn. If the ques­tion was exploratory in nature, the discussion focuses on broad­ening the issues investigated. The

July-September 1999 231

exploration may lead to sugges­tions for future studies. Explana­tory questions can be discussed by placing the results in the pro­posed theoretical construct. The discussion can result in support for the theoretical construct or questioning of the construct. Many authors indicate that a lim­itation of the case study is that results cannot be generalized to the population at large, because it is not possible that one individ­ual can represent a larger group. Replication of results in other cases or under systematically al­tered conditions can enhance the external validity of the case stud­ies.5,9

Ethical Considerations

Two opposing views were found regarding ethical issues in single case reports and designs. McEwen/ in a guide to writing case reports, indicates that pa­tient consent is required from each patient engaged in treat­ment. Additional consent for the case report is not recommended. Keep in mind that case reports do not include an experimental de­sign manipulating the research setting. Bloom et al. 6 describe case study designs that include manipulation of the research set­ting, for which informed consent specific to the research design is needed. Their recommendations are consistent with requirements found in the applications for approval defined by research institutions to protect research subjects from harm. It is recom­mended that each case study in­quiry include details of how in­formed consent was obtained from the subject, be it a single pa­tient or another entity under in­vestigation. Paramount in any in­quiry is the requirement that no harm be done to the subject who helps us further our profession.

Applications in Hand Therapy

Three published case inquir­ies show the use of case reports and case studies. McClure and Flowers 10 illustrate their theory of clinical reasoning in the case re-

port of a 57-year-old medical sec­retary with a limitation in shoul­der motion. Theoretical clinical reasoning is presented with a de­tailed description of the treat­ment and results. The study can be considered explanatory, be­cause it addresses how the re­sults can be explained in terms of the presented theory. Nakada and Uchida7 describe the effects of the application of a five-stage sensory re-education program on the rehabilitation of a 61-year­old woman with leprosy. The study can be considered descrip­tive, because it describes the re­sults of the implemented treat­ment program.

Neeman and Neeman9 inves­tigate the effect of orthokinetic orthoses on elbow range of mo­tion in a patient with a right­sided hemiparesis, using a single­case study design. The study method includes a single-subject time series design to manipulate the independent variable, the

Case inquiries above all help us explore and discuss our treatments.

use of orthokinetic orthoses. Phases of nontreatment, placebo treatment, sham treatment, and orthokinetic treatment are in­cluded in the design. The study reports the effects of the or­thoses and also provides an ex­planation of how the method of single-case design can be used to provide scientific evidence for our interventions.

Summary and Conclusion

Issues of the theory and methodology of case reports and case studies have been presented. Examples of applications of tech­niques used in the rehabilitation of the upper extremity conclude this report in pocket format on the theory and methodology of case reports and case studies.

232 JOURNAL OF HAND THERAPY

Case reports and studies enhance our knowledge about practice in ways that are unique to each case, which are not possible when investigations are per­formed through group compari­son. Case inquiries help us share our practice, sharpen our theoret­ical reasoning, develop our good habits of applying reliable and valid measurements, and above all help us explore and discuss our treatments.

CAROLINE W. STEGINK JANSEN, PHD, PT

The author thanks Kenneth J. Otten­bacher, PhD, OTR, FAOTA, and Kurt M. Mossberg, PhD, PT, for their invaluable comments during the preparation of this manuscript.

References

1. Parkinson P. An essay on the shaking palsy. London, England: Sherwood, Neely and Jones, 1817.

2. Ottenbacher KJ. Clinically relevant designs for rehabilitation research: the idiographic model. Am J Phys Med Rehabil. 1990;69(6):286-92.

3. McEwen I. Writing case reports: a how-to manual for clinicians. Alex­andria, Va .: American Physical Ther­apy Association, 1996.

4. Yin RK. Case Study Research: De­signs and Methods. 2nd ed. Applied Social Research Methods Series, vol. 5. London, England: Sage Publishers, 1994.

5. Portney LG, Watkins MP. Founda­tions of Clinical Research: Applica­tions to Practice. Norwalk, Conn.: Appleton and Lange, 1993.

6. Bloom M, Fisher ], Orme JG. Evalu­ating Practice: Guidelines for the Ac­countable Professional. 2nd ed. Bos­ton, Mass. : Allyn and Bacon, 1995.

7. Nakada M, Uchida H. Case study of a five-stage sensory reeducation pro­gram. J Hand Ther. 1997;10:232-9.

8. Ottenbacher KJ. Analysis of data in idiographic research: issues and methods. Am J Phys Med Rehabil. 1992;71 (4):202-8.

9. Neeman RL, Neeman M. Rehabilita­tion of a post-stroke patient with up­per extremity hemiparetic movement dysfunctions by orthokinetic or­thoses. ] Hand Ther. 1992;10:147-55.

10. McClure PW, Flowers KR. Treatment of limited shoulder motion: a case study based on biomechanical con­siderations. Phys Ther. 1992;72:929-36.

Correspondence and reprint requests to Caroline W. Stegink Jansen, PhD, PT, University of Texas Medical Branch, De­partment of Physical Therapy, 301 Uni­versity Boulevard, Galveston, TX 77555-1028.