entitled "Metacarpophalangeal Joint Replacement: Case Report of 20-Year Follow-Up," provides an excellent study of one patient, documents changes over time, and allows the author an appropriate forum for discussion and stimulation of further in vestigation based on a single subject. Clinical research is difficult to perform and difficult to interpret. Often only a small number of subjects or a single subject is available for testing. Experimental designs and clinical reports must be appropriate for such conditions. It should be clear that a case study of one subject is no less valuable and no less en lightening than is a comparison of experimental groups and is sometimes a more realistic approach to clinical investigation. ROGER A. MUZII, RPT Department of Movement Sciences Box 199, Teachers College Columbia University New York, NY 10027
SUSAN R. HARRIS 5235 18th Avenue NE Seattle, WA 98105
REFERENCE 1. Bleck EE, Nagel DA (eds): Physically Handicapped Children: A Medical Atlas for Teachers. New York, Grune & Stratton, Inc, 1975
Feedback on Biofeedback To the Editor: A clinical report, "Application of Electromy ographic Biofeedback Following Medial Meniscec tomy" by Sprenger, Carlson, and Wessman ( PHYSI CAL THERAPY, February 1979), cites raw data on the use of biofeedback for postmeniscectomy rehabilita tion. This report compares one patient receiving bio feedback with four patients not receiving biofeed back. No statistical analysis of data is included to demonstrate any significant difference between the groups. Thus, the authors' inferences regarding the efficacy of biofeedback are tenuous at best. In such a quasi-experimental design, it is inappropriate to as sume differences between two samples of subjects. The authors' statements that ".. .the patient receiving biofeedback made the most significant net gain in extension as an inpatient," and that "similar improve ments had taken comparable patients longer to achieve" have little validity. There is no evidence that the differences between patients was greater than that attributable to random chance. One could imagine the difficulty in finding a suitable number of wellmatched subjects to provide an experimental group suited to standard statistical analyses or finding sta tistical procedures appropriate for the data collected in this report. An obvious alternative was used by Hebert in PHYSICAL THERAPY, March 1979. This case report, 898
The Author Responds: We appreciate the opportunity to respond to Mr. Muzii's letter. The paper in question was submitted to PHYSICAL THERAPY under the category of "Brief Reports," as defmed on page 1 of the APTA Style Manual. Spe cifically, a "Clinical Report" in this category is in tended to present . .useful ideas, suggestions, or observations and may contain opinions or impres sions" regarding current clinical practice or treatment methods. Our intent was to share our "observations" and "impressions" regarding the clinical application of biofeedback for muscle reeducation purposes. We believe that we observed heightened motivational reaction in response to both the auditory and visual feedback that the units provided the patient. The biofeedback, in our opinion, contributed to more rapid and complete knee extension than was observed in a group of patients with a similar diagnosis. The group had undergone a similar treatment regimen, except for biofeedback. We did not believe that the population sample was adequate to justify an analysis of data. Such statistical treatment of the data would have then qualified this paper to be a lead article, as defined by the Style Manual. To the extent that the paper described a potentially useful motivational treatment method, in cluding the use of biofeedback as a home treatment method, we submitted the manuscript as a "Clinical Report." If our style and format of presentation confused readers by a "quasi-experimental" design, we apolo gize. This is the style of data collection and writing to PHYSICAL THERAPY
Downloaded from https://academic.oup.com/ptj/article-abstract/59/7/898/4560012 by University of Texas at Dallas user on 04 February 2019
bral palsied children in pool therapy that a pool temperature of less than 95° F will cause an increase in muscle tone. Although the descriptions of impairments and dis abilities in Adapted Aquatics appears to be fairly thorough and accurate, there is no systematic attempt to recommend specific swimming techniques for spe cific handicapping conditions, as was attempted in my article. I wholeheartedly agree with Ms. Priest's statement that "interdisciplinary cooperation is absolutely es sential" in the field of adapted aquatics. It was not the intent of my article to in any way hinder this cooperation but rather to present some alternative strategies for teaching swimming to handicapped chil dren that would be of value to both physical therapists and swimming instructors.
SUSAN R. HARRIS 5235 18th Avenue NE Seattle, WA 98105
REFERENCE 1. Bleck EE, Nagel DA (eds): Physically Handicapped Children: A Medical Atlas for Teachers. New York, Grune & Stratton, Inc, 1975
Feedback on Biofeedback To the Editor: A clinical report, "Application of Electromy ographic Biofeedback Following Medial Meniscec tomy" by Sprenger, Carlson, and Wessman ( PHYSI CAL THERAPY, February 1979), cites raw data on the use of biofeedback for postmeniscectomy rehabilita tion. This report compares one patient receiving bio feedback with four patients not receiving biofeed back. No statistical analysis of data is included to demonstrate any significant difference between the groups. Thus, the authors' inferences regarding the efficacy of biofeedback are tenuous at best. In such a quasi-experimental design, it is inappropriate to as sume differences between two samples of subjects. The authors' statements that ".. .the patient receiving biofeedback made the most significant net gain in extension as an inpatient," and that "similar improve ments had taken comparable patients longer to achieve" have little validity. There is no evidence that the differences between patients was greater than that attributable to random chance. One could imagine the difficulty in finding a suitable number of wellmatched subjects to provide an experimental group suited to standard statistical analyses or finding sta tistical procedures appropriate for the data collected in this report. An obvious alternative was used by Hebert in PHYSICAL THERAPY, March 1979. This case report, 898
The Author Responds: We appreciate the opportunity to respond to Mr. Muzii's letter. The paper in question was submitted to PHYSICAL THERAPY under the category of "Brief Reports," as defmed on page 1 of the APTA Style Manual. Spe cifically, a "Clinical Report" in this category is in tended to present . .useful ideas, suggestions, or observations and may contain opinions or impres sions" regarding current clinical practice or treatment methods. Our intent was to share our "observations" and "impressions" regarding the clinical application of biofeedback for muscle reeducation purposes. We believe that we observed heightened motivational reaction in response to both the auditory and visual feedback that the units provided the patient. The biofeedback, in our opinion, contributed to more rapid and complete knee extension than was observed in a group of patients with a similar diagnosis. The group had undergone a similar treatment regimen, except for biofeedback. We did not believe that the population sample was adequate to justify an analysis of data. Such statistical treatment of the data would have then qualified this paper to be a lead article, as defined by the Style Manual. To the extent that the paper described a potentially useful motivational treatment method, in cluding the use of biofeedback as a home treatment method, we submitted the manuscript as a "Clinical Report." If our style and format of presentation confused readers by a "quasi-experimental" design, we apolo gize. This is the style of data collection and writing to PHYSICAL THERAPY
Downloaded from https://academic.oup.com/ptj/article-abstract/59/7/898/4560012 by University of Texas at Dallas user on 04 February 2019
bral palsied children in pool therapy that a pool temperature of less than 95° F will cause an increase in muscle tone. Although the descriptions of impairments and dis abilities in Adapted Aquatics appears to be fairly thorough and accurate, there is no systematic attempt to recommend specific swimming techniques for spe cific handicapping conditions, as was attempted in my article. I wholeheartedly agree with Ms. Priest's statement that "interdisciplinary cooperation is absolutely es sential" in the field of adapted aquatics. It was not the intent of my article to in any way hinder this cooperation but rather to present some alternative strategies for teaching swimming to handicapped chil dren that would be of value to both physical therapists and swimming instructors.
