Theory: the guide to clinical practice and research.

One hallmark of a profession is a unique core of knowledge. Professional knowledge arises from research central to the concerns of those who practice the profession. For the engineer, research focuses on how matter and energy can be utilized; for the lawyer, research centers on issues of justice; for the physical therapist, research is concentrated on understanding physical movement, including its pathologies and treatment, and concerns about communication in the clinical setting. During the past 10 years, there has been a dramatic increase in physical therapy research as evidenced by the number and breadth of research studies published in Physical Therapy, presented at American Physical Therapy Association (APTA) Combined Sections Meetings and Annual Conferences, and funded by The Foundation for Physical Therapy Inc. Concurrently, physical therapists have struggled to identify the core of knowledge upon which their practice is established. How are physical therapists different from exercise physiologists, kinesiologists, and physiatrists? Are their research programs leading them to develop and test knowledge that is unique to physical therapy practice? From several sources, physical therapy educators and practitioners are hearing that a significant element in the development of a core of knowledge is too often missing in research reports. Articles published in physical therapy journals, organizers of conferences, and various hearings have focused on encouraging researchers to include this missing element: theory. Research that focuses on studies of the mechanical tools of physical therapy or that is limited by a too-narrow view of what constitutes valid research methods does not favor the development of this core of knowledge. Although much of this research is very good, it is limited in its usefulness to the practitioner. For example, there are numerous studies on the reliability and validity of instruments such as goniometers and electrical stimulators that lack an underlying explanatory framework and thus do not lead to new areas of research. Second, researchers overly rely on methodologies, be they descriptive, quasi-experimental, or experimental, that produce data that can be analyzed statistically. Although statistical studies are appropriate for many important research questions, a reluctance to use other analytical procedures limits the growth of the field. There are too few studies that are designed, for example, to examine patients and practices longitudinally and too few studies of intervention and outcome for patients with complex conditions such as neurologically involved children or frail elders. Although each piece of research contributed by physical therapists does add to the collective knowledge of certain aspects of the practice, the sum of this atheoretical research does not advance an integrated understanding of the complex interplay among body systems in normal and pathological states or the overlay of pain and social factors that influence human movement and function. if research continues to be limited in these ways, the goal of a distinctive core of physical therapy knowledge will not be met. For many years, the typical physical therapy research report has begun with a brief discussion of prior studies to which the present study is related, followed by a presentation of the design and procedures of the study, and concluding with a discussion of the results of the study and exhortations to carry out more such studies on more subjects in more settings. Absent in such reports is a presentation of the theory underlying the research questions. As a result, authors are unable to connect their work with what is known in a meaningful way and they are unable to draw logical implications for future research. Without the connectedness of theory, researchers are equally unable to challenge longstanding beliefs related to practice. One of the impediments to the use of theory in research and practice is, we believe, a failure to understand what theory is. For some, theory is seen as the synthesis of previous research studies on a given topic. For others, theory is taken as diffuse and self-evident statements such as "Application of cold reduces swelling." Amplification of this theory," such as what circumstances must prevail for it to be true (scope conditions), what other propositions relate to this one, and so forth, is omitted. For still other professionals, theory is thought to reside in dusty tomes that are properly ignored because theory is believed to have little relevance to clinical practice. People who choose active, involving, practical avenues of work such as physical therapy are often impatient with the notion of theory. As students, they want and who can blame them?) to absorb the kind of information that can be put to immediate use, whether it be learning a new modality purported to relieve pain, observing a new technique that promises to accelerate a child's sitting balance, or manipulating an adjustable orthosis to provide optimal equilibrium between stability and flexibility. As educators and practitioners, physical therapists attend conferences, enroll in continuing education courses, read journals, and consult with colleagues, ever on the lookout for good ideas that can be quickly and efficiently applied to practical settings. Too often, physical therapists are much less interested in why things happen the way they do than in discovering bow to effect desired results. Over time, physical therapists add to their repertoires of skills or "bags of tricks." Sometimes a trick will work: the pain will be relieved, the child will sit up more quickly, a patient's gait will improve ... and sometimes those things will not happen. Therapists have no way of determining why a procedure works (or does not), because a framework connecting the critical elements of and explaining the phenomenon is missing. In the absence of such a framework, therapists are hampered in their efforts to invent sensible solutions to clinical challenges; they have less power than they might to control decisions in clinical practice. The framework they are missing is theory. Nonetheless, physical therapists are beginning to recognize the importance of theory. In a recent article in Physical Therapy, Krebs and Harris stated, "Theory presentation is perhaps the most important contribution a professional can make to the literature in his or her field.(1)(p690) At the 1988 Joint Congress of the APTA and the Canadian Physiotherapy Association in Las Vegas, Nev, an open forum on theory was presented by the then-active APTA Committee on Research. During this forum, enthusiastic participants discussed the working document "Goals and Objectives for Development of Theory in Physical Therapy." One result of the forum is the requirement that manuscripts submitted to Physical Therapy be reviewed for the inclusion of a theoretical framework. We hope that this article will add to the understanding and use of theory and continue the theoretical conversation. The purposes of this article are to define theory and to give some general as well as physical therapy examples of how theory is and can be used to guide clinical thinking and research. What is Theory? Theory is a word encompassing two concepts: contemplation and observation. (The Greek root for theory, thea, meaning "a viewing," is also the root for theater.) Through contemplation and observation, theories or ideas about how things relate are developed. A theory, then, is a distillation of diverse experiences and notions such that they can be tied together in a sensible and powerful bundle. in other words, theory is a system of wide-ranging ideas about some centrally important physical or social issue. Because theory is built on and consists of ideas, it is by nature abstract. This can be irksome for many physical therapy professionals, particularly those who are committed to and find most rewarding the "hands-on" aspect of physical therapy. If something is abstract, they reason, it is not relevant to clinicians who are faced with doing something, now. To the contrary, we shall argue that it is theory's very abstractness that makes it especially relevant to the clinician. Perhaps an analogy is in order. Consider the frozen-foods section of the supermarket. There you may select concentrates of apple, orange, lemon, grape, and many other fruits. From a lemon concentrate, for example, one can make lemonade by adding water, a lemon cake by substituting the lemon concentrate for water, lemon popsicles by adding water and freezing the resulting liquid, salad dressing by using the concentrate as the acetic ingredient, and so on. On the other hand, very few, if any, people would consume the lemon concentrate by itself. In the same way, theories are seldom, if ever, usefull by themselves; they are useful when they are applied in practical situations. If the concentrate is the theory and the lemonade, lemon cake, lemon popsicle, and salad dressing are the practical situations, one can readily see how much more versatile the concentrate is than any one of its products. To delve a little deeper, by contemplating the lemon concentrate further, one can see that it is an acetic substance that can be used in any situation wherein an edible acid might be needed. Earlier we stated that a theory is sensible and powerful, that it consists of a system of wide-ranging ideas about some important issue. In the lemon-concentrate example, the concentrate represents the sensibleness and system of the definition; the products in which it is used represent the power and wide-ranging aspect of the definition. The acetic quality of the concentrate underlies its importance; understanding this, the consumer is free to invent uses and apply the concentrate to an infinite number of practical concerns. Thus, theory connects to practical situations just as the concentrate connects the lemon with lemonade; theory connects the past with the present and the future. just as the concentrate is the basis for the creation of many products, theory lays the groundwork for many sensible and inventive approaches to practical issues. In sum, theory provides both a perspective for understanding and a basis for effective action. Earlier we asserted that a theory is a set of wide-ranging ideas about some physically or socially significant phenomenon, that theories connect ideas in a way that helps people understand phenomena and that helps guide people's practical decisions. Theories have existed and have been used throughout recorded history. They are dynamic in that they evolve as new insights are added to a profession's body of knowledge. What is the meaning of theory for physical therapy? Use of Theory in Clinical Practice Upon examination, one discovers that the practice of physical therapy has a shape." For some, the shape is more defined than for others; nonetheless, a form is discernible. This shape is determined by the theories (systems of wide-ranging ideas) physical therapists hold about the construction and function of the human body. Physical therapists, as do other health care professionals, evaluate and treat patients according to the usually implicit theories they hold. For example, is the movement from lying to standing based on the evolution of righting abilities in the maturing child (theory of maturation of righting abilities) or does there exist a life-span evolution of movement (theory of evolution across individuals and time)?(2) If one practiced according to the tenets of the theory of maturation of righting abilities, one would teach an elderly person to come from lying to standing using the same movement sequence a typical 6-year-old child would use. Alternatively, if one practiced according to the tenets of the life-span evolution theory, one would teach an elderly person to rise using any one of a number of movement sequences based on the patient's age, flexibility, and body shape. In another example of how theory is intimately tied to practice, consider soft tissue swelling. Can the swelling resulting from a sprained ankle be decreased by the application of cold, based on the theory that cold minimizes the inflammatory process, or by alternate applications of heat and cold, based on the theory that alternating vasodilation and vasoconstriction results in a pumping action that removes excess fluid?(3) Depending on which theory the therapist uses, the patient would receive either cold treatment or alternating heat and cold treatments. If these theories were systematically tested and appropriately revised, it is possible that one theory would hold for some conditions in which swelling injuries occur whereas the other theory would suit different conditions of injury. The different conditions of injury are an example of scope conditions that delimit the situations in which the theory can be expected to be useful. When a treatment does not work as expected, a therapist aware of the power and usefulness of theory, after ruling out more immediate causes, might ask whether the conditions under which the treatment is supposed to work (ie, the theory underlying it) have been met. If so, perhaps the theory needs revision-If not, perhaps the application of another theory would be in order. If the foregoing argument is accepted, the reader should be persuaded that theory is neither irrelevant nor esoteric. The problem facing many practice-oriented professions is that clinicians are too often unaware of what theories they are using and how these theories are helpful. Thus, a given individual's practice may lack coherence and may even contain contradictions. If clinicians do not know and do not reflect upon the theories they are using, treatments may be inadvertently misadministered, It is possible that therapists can intuitively develop integrated notions of treatment that are theoretically, if tacitly, sound. Some have, and they are among those clinicians who are most admired. If theoretic continuity remains the province of individual practitioners who do not communicate regularly with the profession as a whole, however, the profession itself will not continue to develop as it should. The importance of theory and its use must be made explicit and a part of each therapist's professional life, from the point of entry into educational programs until retirement from active practice. How can physical therapists best continue moving toward the goal of developing a core of knowledge and expanding themselves as professionals? The answer, we believe, lies in how physical therapy research studies are conceptualized and shared. Use of Theory in Clinical Research Theories can develop in a number of ways. Most scientific theories have developed through logical speculation about some problematic situation. These theories are not grounded in experience. Once developed, such a theory or system of ideas about some phenomenon is subjected to testing in the "real world." The testing entails the derivation of hypotheses or tentative explanations of the phenomenon and the assessment through statistical analysis of the probability that the hypotheses are correct. Theories whose hypotheses are not falsified are taken to be provisionally adequate explanations of the phenomena the cover.(4) Theories whose hypotheses are falsified through experimentation are revised or discarded in favor of more promising theories. Such hypothetico-deductive theories have been discussed by Krebs and Harris.(1) Theories can also develop through the accretion of experience. By reflecting upon experience, it is possible to note patterns that can be developed into systematic ideas about phenomena. This kind of theory development and use is called "grounded theory" by Glaser and Strauss(5) and is gaining currency in many disciplines and professional fields. To continue this section, we will briefly discuss the way these two types of theory can be used to guide research studies. Consider, for example, the phenomenon of health care compliance or patient cooperation. A researcher is interested in why some patients follow the regimen recommended by their physical therapists and why others do not or do so to a much lesser degree. According the social learning theory-a hypothetico-deductive theory-people organize their behaviors with respect to the rewards available in the environment: The more rewarding a behavior is, the more likely one is to repeat it. The researcher might hypothesize that compliance will be highest among those patients for whom wellness is most central (ie, rewarding). Thus, the researcher would predict that professional athletes will comply more readily than "weekend warriors" to home programs designed to remediate pulled hamstring muscles. The researcher would reason that a professional baseball player cannot play (and thus gain glory and secure free-agent status) with a dysfunctional hamstring muscle, whereas an accountant can professionally advance with or without an injured hamstring muscle. Similarly, the researcher would expect a sculptor to be more compliant with a home exercise program for rheumatoid arthritis than a department store executive. Having formulated a theory-based hypothesis, the researcher would design a study to test the hypothesis that a relationship exists between centrality of dysfunction and compliance with home exercise programs. The researcher would attend carefully to the concepts of centrality" and dysfunction." Does centrality refer to the importance of wellness for one's vocational life, one's social life, or both? Does centrality refer to the quality of one's life generally, and, if so, how shall quality" be defined? With respect to the concept of dysfunction, the researcher will perhaps decide on levels of acuteness and rule out genetic predispositions. The careful definition of concepts and specification of their relationship as guided by theory will yield a greater understanding of physical therapy phenomena. it should be clear that an abstract theory can yield many types of research questions and many testable hypotheses. This use of theory follows a deductive approach in which the theory guides the development of testable hypotheses. Another way to use theory is explicitly to ask theoretical questions of clinical practice. Suppose, for example, a therapist notices that, even though professional athletes generally comply more readily than accountants with home exercise programs, not all professional athletes comply and not all accountants fail to comply. What is going on here? To answer this question, the therapist-researcher might identify groups of earnest compliers and noncompliers and carefully observe and interview them across a variety of settings: in a clinic with a physical therapist, with a physician, at home, at work, and at leisure. The study would focus on discovering patterns that distinguish people exhibiting different degrees of compliance. The theory guiding this effort does not predict behavior under specific circumstances; rather, it assumes that people behave in patterned ways, and the researcher is interested in discovering those patterns. Basic to such patterns are the meanings people give to their therapeutic circumstances and how meanings are transformed into compliant (or noncompliant) behavior. With such knowledge, researchers and therapists can develop different ways of establishing home exercise programs for different patients. in the lemon-concentrate analogy, it was argued that an understanding of acetic concentrates empowered its users to apply that understanding in many and varied circumstances. Consider now the gate-control theory of pain that was proposed by Melzack and Wall in 1965.(6) In 1987, Wang and Freeman stated

Some of the specifics of the gate control

theory have been found to be

incorrect. However, the concept underlying

its mode of action, which is that

pain fiber input to the brain can be

reduced or eliminated by the activity of

other neuronal pathways, has been

substantiated and used to develop therapies

for the treatment of chronic

pain.(7)(p75) As a result of understanding the theory-an explanation of pain-physical therapists can use modalities as diverse as ice, electrical stimulation, and acupuncture to control pain. Additionally, because the gate-control theory allows for pain control from both ascending and descending fibers, the discovery of endogenous morphinelike substances (eg, endorphins) within the central nervous system opens up new possibilities for pain control. In this example, the gatecontrol mechanism is analogous to the lemon concentrate, the physical therapy modalities are analogous to the lemon products, and the possibility of self-stimulation of endorphins for pain relief is analogous to an understanding of lemon concentrate as an edible acetic acid. As Michels has stated, "Research without theory does not contribute to knowledge."(8)(p134) By using theory as a searchlight to guide thinking and focus questions about physical therapy problems, a sustained program of research can be pursued. The use of theory invites the researcher-practitioner to look deeper into specific phenomena and to ask how such phenomena are connected with other phenomena. It allows questions about why something works; under what conditions; and with what pathological states, modified by what confounding variables. As the theoretical base for physical therapy practice and research grows, so will physical therapy continue to develop as a distinct and socially valued profession. Acknowledgment We thank Gail Jensen, PhD, PT, for her thoughtful contributions and enthusiastic support throughout the development of this article. References 1 Krebs DE, Harris SR. Elements of theory presentations in physical therapy. Phys Ther. 1988;68:690-693. 2 VanSant AF. Age differences in movement patterns used by children to rise from a supine position to erect stance. Phys Ther. 1988;68:1330-1338. 3 Cotig D), Prentice WE jr, Hooker DN, Shields EW. Comparison of three treatment procedures for minimizing ankle sprain swelling. Phys Ther, 1988;68:1072-1076. 4 Popper K. Objective Knowledge: An Evolutionary Approach. Oxford, England: Oxford University Press; 1974. 5 Glaser B, Strauss A. The Discovery of Grounded Tbeory. Chicago, Ill: Aldine Publishing Co; 1967. 6 Melzack R, Wall PD, Pain mechanisms: a new theory. Science. 1965;150:971-979. 7 Wang M, Freeman A. Neural Function. Boston, Mass: Little, Brown & Co Inc; 1989. 8 Michels E. Enhancing the scholarly base: the role of faculty in enhancing scholarship. J Allied Health. 1989;18:129-142. J Tammivaara, PhD, is Associate Professor of Doctoral Studies in Education, Gonzaga University, Spokane, WA 99258 (USA). Address all correspondence to Dr Tammivaara. K Shepard, PhD, PT, FAPTA, is Associate Professor, Department of Physical Therapy, College of Allied Health Professions, Temple University, Philadelphia, PA, 19140. This article was submitted August 24, 1989, and was accepted May 16, 1990.