Physical Therapy: Evidence Based Physical Therapy (EBPT)

Evidence-based physical therapy (EBPT) has been defined as "physiotherapy informed by relevant high quality clinical research" (Herbert, Jamtvedt, Mead & Hagen, 2005, p. 1). "The practice of evidence-based physiotherapy should be informed by the integration of relevant high quality clinical research, patients' preferences and physiotherapists' practice knowledge" (Herbert, p. 2). In the event that high quality clinical research is not available, good practice must make use of other sources of information such as peers, practice guidelines, practice knowledge, and any other lower quality research to inform action in practice.  

Why Practice EBPT?

The practice of EBPT really comes from making the "cost effectiveness of physiotherapeutic intervention in comparison with other ... treatment, or no treatment at all" make clinical sense (Koes, 1997). Another reason for the existence of EBPT, is because it is "the best strategy clinicians can use to cope with the potential chaos and uncertainty of modern clinical practice, and to meet the ethical imperative of providing the best possible care for our patients" (Sherrington, Moseley & Herbert, 2001, p. 125).

Goals of EBPT     

• make sure that all decisions made for patient care take into account "the best available evidence."
• better plan and evaluate service delivery.
• better analyze research studies and direct those findings to better care.
• take better measurement and do interpretation of outcomes to provide the best care possible.
• provide better patient information.
• better understand the reasons for lack of compliance by patients in relation to their PT care.
• accurately gauge the relationship between patients and physical therapists and its effect on health-related outcomes.
• develop theories based on evidence in practice.

EBPT History

Since the early 1990's, following the rise of Evidence-Based Medicine (EBM), the concept of evidence-based practice has been associated with physical therapy. The first publication on this topic came out of the Department of Epidemiology at the University of Maatricht, Netherlands. Today, the major study center is the Centre for Evidence-Based Physiotherapy based in the School of Physiotherapy at the University of Sydney, Australia.

1. Ask: Convert the need for information into an answerable question.

A question is considered well-built if it addresses the most pertinent parts of your information need and will lead to a focused answer for your clinical question:

EB-PT (or OT)  uses the PICO model for formulating a clinical question:

P = Population or Problem - recipients or potential beneficiaries of a service or intervention, or the situation being examined

I = Intervention or exposure - the service or planned action to be delivered to the population

C = Comparison - an alternative service or action that may or may not achieve similar outcomes

O = Outcome - the ways in which the service or action can be measured to establish whether it has had a desired effect

2. Find: Track down the best evidence with which to answer that question.

Steps in a Good Search

1. Construct the question (see previous section).
2. Select the best resource (see Resources for some places to start).
3. Formulate the search strategy.

Think about the keywords for each part of the clinical question:

For the question: Is prophylactic physical therapy for patients undergoing upper abdominal surgery effective in preventing post-operative pulmonary complications?

A search strategy might include:

3. Appraise: Critically appraise that evidence for its validity and applicability.

(From Most Valuable to Least Valuable)

1. Meta-analyses: Methods of synthesizing the data from more than one study, in order to produce a summary statistic
2. Systematic Review: [tries] to answer a clear question by finding and describing all published, and if possible, unpublished work, on a topic. [It] uses explicit methods to perform a thorough literature search and critical appraisal of individual studies and uses appropriate statistical techniques to combine these valid studies (Booth & Brice, 2004).
3. Randomized Controlled Trials (RCT): are also called 'randomized clinical trials.' They involve the random assignment of subjects to groups   that are then given different interventions to assess the effects of the interventions.
4. Controlled Comparison or Case Control Study: is an observational study in which the cases have the issue of interest
5. Descriptive Surveys: studies aimed at describing certain attributes of a population, specifying associations between variables, or searching out hypotheses to be tested, but which are not primarily intended for establishing cause-and-effect relationships or actually testing hypotheses.
6. Case Studies: describe a particular service or event, often focusing on unusual aspects of the reported situation or adverse occurrences, commonly have exploratory, descriptive, or explanatory purposes.

Evaluation criteria are:

1. Credibility (Internal Validity)
2. Transferability (External Validity)
3. Dependability (Reliability)
4. Confirmability (Objectivity)

Credibility: looks at truth and quality and asks, "Can you believe the results?"

Some questions you might ask are: Were patients randomized? Were patients analyzed in the groups to which they were (originally) randomized? Were patients in the treatment and control groups similar with respect to known prognostic factors?

Transferability: looks at external validity of the data and asks, "Can the results be transferred to other situations?"

Some questions you might ask are: Were patients in the treatment and control groups similar with respect to known prognostic factors? Was there a blind comparison with an independent gold standard? Were objective and unbiased outcome criteria used? Are the results of this study valid?

Dependability: looks at consistency of results and asks, "Would the results be similar if the study was repeated with the same subjects in a similar context?"

Some questions you might ask are: Aside from the experimental intervention, were the groups treated equally? Was follow-up complete? Was the sample of patients representative? Were the patients sufficiently homogeneous with respect to prognostic factors?

Confirmability: looks at neutrality and asks, "Was there an attempt to enhance objectivity by reducing research bias?"

Some questions you might ask are: Were 5 important groups (patients, care givers, collectors of outcome data, adjudicators of outcome, data analysis) aware of group allocations? Was randomization concealed?

4. Apply: Integrate the critical appraisal with clinical expertise and with the patient's unique biology, values, and circumstances.

Guidelines for applying evidence in clinical practice can be found in the classic text:

Guyatt, G., Rennie, D., Meade, M., and Cook, D. (2008) Users' guides to the medical literature: a manual for evidence-based clinical practice (2^nd ed.). New York, NY: McGraw-Hill Professional.

Chapters in this guide are organized by type of clinical question: therapy, harm, diagnosis, and prognosis.

Other good resources for both appraisal and applying evidence in clinical practice can be found on these two websites:

KT Clearinghouse/Centre for Evidence-Based Medicine, Toronto:
http://ktclearinghouse.ca/cebm/teaching/worksheets

Centre for Evidence Based Medicine, University of Oxford:
http://www.cebm.net/index.aspx?o=1157

5. Evaluate: Evaluate the effectiveness and efficiency in executing steps 1-4 and seek ways to improve them both for next time.

Ask yourself:

1. Did you ask an answerable clinical question?
2. Did you find the best external evidence?
3. Did you critically appraise the evidence and evaluate it for its validity and potential usefulness?
4. Did you integrate critical appraisal of the best available external evidence from systematic research with individual clinical expertise in personal daily clinical practice?