Evidence Based Practice

Amir H. BakhtiaryPhD in PhysiotherapyAssociate Professor

Musculoskeletal Rehabilitation Research Center

Definition: Evidence based practice is using best research evidence available along with clinical expertise and patient values to inform decisions regarding clinical practice. (Sackett 1998, 2000)Research evidence refers to 'clinically relevant research' and especially that evidence derived from clinical research that is patient centered, that evaluates the accuracy and precisions of test and prognostic markers and the efficacy and safery of therapeutic, rehabilitative and preventative interventions. (Sackett, 1998)

Definition: Evidence based practice is using best research evidence available along with clinical expertise and patient values to inform decisions regarding clinical practice. (Sackett 1998, 2000)

Clinical expertise is the proficiency and judgment that each clinician acquires through clinical experience and practice.  Patient values refers to the unique preferences, concerns and expectations of each patient.

www.cebm.netWhat is evidence-based medicine?

“Evidence-based medicine is the integration of best research evidence with clinical expertise and patient values”

Patient Concerns

Clinical Expertise

Best research evidenceEBM

Dave Sackett

Here is another way to think about Evidence Based Practice:Therapist considers:•person, •task, •environment •and evidence and uses: •clinical reasoning •judgement •and experience to make a decision regarding best practice management and intervention. (Thomas, 2004)

Evidence based practice has 5 steps:1. Convert the need for information into clinically

relevant, answerable questions. 2. Find, in the most efficient way, the best evidence

with which to answer these questions. 3. Critically appraise the evidence for its validity 4. Integrate the appraisal with clinical expertise and

apply the results to clinical practice. 5. Evaluate your efficiency and effectiveness in

finding the evidence and applying it.

1- Convert the need for information into clinically relevant, answerable questions.

Asking the right question Formulating clear, focused clinical questions is a prerequisite to answering them. (Sackett, 1998). To formulate the question Sackett suggests to break it down into 4 components:

Person or problem of interest (population) Intervention Comparison OutcomeThis is called a PICO format and using this strategy will help you to

think systematically about exactly what kind of information you are looking for and get specific search results.

Here is an example of a PICO search question:'In children with Cerebral Palsy (population), can physiotherapy

(intervention) assist to increase strength in lower limbs (outcome), compare to no physiotherapy intervention (comparison)?

2-Find, in the most efficient way, the best evidence with which to answer these questions.

Finding the evidence After you have formulated the question it is time to start searching for the evidence.

The best way to do this is to use the available databases that list information about literature on certain topics. There are a wide variety of data bases available, that all have a different focus area.

A good place to start is accessing the library services. Some examples of their databases are: Pubmed (Exceptional Child Education Resources), CINAHL (Cumulative Index to Nursing and Alllied Health) and Iranian National Medical Digital Library or Inlm (ww.inlm.org)

3- Critically appraise the evidence for its validity

Critical appraisal of the evidence Once the evidence has been found, it has to be critically appraised and its validity and usefulness determined (Sackett, 1998).

Level 1a evidence Systematic review of all relevant randomized controlled trials (RCT).

Level 1b evidence Individual RCT

Level 2a evidence Lower quality systematic review incl. both randomised controlled trials and non-randomised controlled trials and cohort studies

Level 2b evidence Individual cohort study (including low quality RCT)

Level 3a evidence Systematic review of case control studies

Level 3b evidence Individual case control study

Level 4 evidence Case series (and poor quality cohort and case-control studies)

Level 5 evidence Expert opinion without explicit critical appraisal, or based on physiology, bench research, text book, or literature review

3-Critically appraise the evidence for its validity (continue)

• Clinical evidence is developed by trying to answer questions related to patients from information gained through research projects or primary studies. From primary studies the evidence pyramid is built up. Each layer of the pyramid is created from evidence derived from the layers below and someone has done the work involved to value-add.

• At times primary studies have been systematically reviewed so all the available evidence from primary studies is reviewed in a single convenient paper: a systematic review.

• Systematic reviews and RCTs have been named the "gold standard' in the literature, i.e that is the level of evidence to aim for. Unfortunately systematic reviews are still rare, so clinicians need to be able to interpret all available evidence.

3 -Critically appraise the evidence for its validity (continue)

• It is important to note that expert opinion is acknowledged as level 5 and this includes unpublished work, conference notes, text book excerpts, etc. Although changing, this is where much of allied health evidence is available at present. (Thomas, 2004)

• Once the available evidence has been critically appraised, it can be summarised in to a Clinically Appraised Topic (CAT): A summary of the best available evidence for a specific clinical question through systematically and critically appraising all the available literature.

4-Integrate the appraisal with clinical expertise and apply the results to clinical practice.

• Applying the evidence Once the available evidence has been critically appraised, it can be applied to clinical practice.

• This involves the essential second element of evidence based practice: integrating the evidence with clinical expertise and knowledge of the unique features of patients (students) and their situations, rights and expectations. (Sackett, 1998).

4-Integrate the appraisal with clinical expertise and apply the results to clinical practice.

• Thomas (2004) described this as the process where a therapist considers the person, task, environment and evidence and uses clinical reasoning, judgement and experience to make a decision regarding best patient management.

• Obviously when applying the new found information to your practice all the normal standards of best practice in educational therapy service delivery (duty of care, risk management, timeliness, educational relevance, etc.) apply.

5- Evaluate your efficiency and effectiveness in finding the evidence and applying it

• Evaluate the process As with any process used it is important to evaluate the first 4 steps in the EBP process. This is particularly so when starting out in using evidence based practice and the skills needed in the process are new and unfamiliar.

• Qld Health CDP, (2005) suggest to ask some simple questions: 1. Am I recording questions as they arise in clinical practice? 2. Am I searching in the most efficient and effective way? 3. Am I appraising the found evidence correctly and critically? 4. Am I applying the evidence and information found in my clinical

practice?• By answering these questions you will ensure that you keep on track

in your quest to find the best available evidence and improve your skills in finding the evidence in an efficient and effective way.