Clista Clanton, MSLS, AHIP August 27, 2009
Clista Clanton, MSLS, AHIP
August 27, 2009
Evidence-Based Practice
Evidence-Based Practice (EBP) requires that decisions about health care are based on the best available, current, valid and relevant evidence. These decisions should be made by those receiving care, informed by the tacit and explicit knowledge of those providing care, within the context of available resources.
Dawes, M., Summerskill, W., Glaszion, P., Cartabellotta, A., Martin, J., Hopayian, K. et al. (2005) Sicily statement on evidence-based practice. BMC Medical Education, 5. Retrieved 7/22/09 from http://www.biomedcentral.com/1472-6920/5/1
Evidence-Based Medicine
"Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research.”
Sackett, D.L. et al. (1996) Evidence based medicine: what it is and what it isn't. BMJ 312 (7023), 13 January, 71-72.
Adapted from: Sackett D.L., Rosenberg M.C., Gray J.A., Haynes R.B., Richardson W.S. (1996). Evidence based medicine: what it is and what it isn't. BMJ, 312, 71-72.
Developing the Clinical Question Step 1: Formulate the clinical issue into a
searchable, answerable question. Step 2: Distinguish what type of question
you may have.
Background
Foreground
Experience with Condition
Background Questions
Background questions ask for general information about a condition or thing. A question root (who, what, when, etc) combined
with a verb. A disorder, test, treatment, or some other form of
healthcare.▪ What causes arthritis?▪ What is the recommended length of exercise for
pregnant women?
Background questions are typically answered by textbooks.
Foreground Questions
Foreground questions ask for specific knowledge about a specific patient with a specific condition.Are specific stabilization exercises any more
effective than general strengthening exercises for low back pain?
Are strengthening exercises contraindicated in people suffering from post polio syndrome?
Foreground questions are typically answered by databases that access the
research literature
Developing the question
Foreground questions usually have four components.
P = Patient population
I = Intervention
C = Comparison
O = Outcome
Patient population/disease The patient population or disease of interest- age- gender- ethnicity- with certain disorder (e.g., hepatitis)
Intervention The intervention or range of interventions of interest- Exposure to disease- Prognostic factor A- Risk behavior (e.g., smoking)
Comparison What you want to compare the intervention against- No disease- Placebo or no intervention/therapy- Prognostic factor B- Absence of risk factor (e.g., non-smoking)
Outcome Outcome of interest- Risk of disease- Accuracy of diagnosis- Rate of occurrence of adverse outcome (e.g., death)
PICO: Components of an answerable, searchable question
Melnyk, B. M., & Fineout-Overholt, E. (2005). Evidence-based practice in nursing & healthcare : A guide to best practice. Philadelphia, PA: Lippincott Williams & Wilkins.
In patient with
[Patient/ Problem]
does
[Intervention]
or
[Comparison, if any]
affect
[Outcome]
In patients with chronic pain, does the use of progressive muscle relaxation lead to a lessening of pain? In patients with post polio syndrome, are strengthening exercises contraindicated?
Is the 6-minute walk test useful in assessing the functional capacity of COPD patients?
In patients with low back pain, are specific stabilization exercises or general strengthening exercises more effective?
Types of Questions Diagnosis: How to select a diagnostic test or how to interpret
the results of a particular test.
Prognosis: What is the patient's likely course of disease, or how to screen for or reduce risk.
Therapy: Which treatment is the most effective, or what is an effective treatment for a particular condition.
Harm or Etiology: Are there harmful effects of a particular treatment, or how these harmful effects can be avoided.
Prevention: How can the patient's risk factors be adjusted to help reduce the risk of disease?
Cost: Looks at cost effectiveness, cost/benefit analysis.
Qualitative: Helps to understand clinical phenomena with emphasis on understanding the experiences and values of patients.
Health Sciences Literature Primary – original
research Experimental (an
intervention is made or variables are manipulated)○ Randomized Control Trials○ Controlled trials
Observational (no intervention or variables are manipulated)○ Cohort studies○ Case-control studies○ Case reports
Secondary – reviews of original research Meta-analysis Meta-synthesis Systematic reviews Practice guidelines Reviews Decision analysis Consensus reports Editorial, commentary
Not used in EBP
Type of Question Suggested Best Type of Study
Therapy RCT > cohort > case control > case series
Diagnosis Prospective, blind comparison to gold standard
Etiology / Harm RCT > cohort > case control > case series
Prognosis Cohort study > case control > case series
Prevention RCT > cohort study > case control > case series
Clinical Exam Prospective, blind comparison to gold standard
Cost Economic analysis
Questions of therapy, etiology and prevention which can best be answered by RCT can also be answered by a meta-analysis or systematic review.
Hierarchy of Evidence
Case Series/Case Reports
Case Control Studies
Cohort Studies
Randomized Controlled Trial
Systematic Review
Meta-analysis/Meta-synthesis
Animal Research/Expert Opinion
Start at the top and work your way down.
Systems
Computerized decision support
Summaries
Dynamed, ACP PIER, Clinical Evidence, EBP guidelines
Synopses
TRIP, ACP Journal Club
Syntheses
Cochrane Systematic Reviews, DARE, PEDro
Studies
PubMed, Scopus, CINAHL
Haynes RB. Of studies, summaries, synopses, and systems: the “5S" evolution of services for finding current best evidence. ACP Journal Club. 2001;134: A11–13.
Adapted from Haynes (2001)
Sources of Information Dynamed Cochrane Library TRIP PEDro National Guideline Clearinghouse PubMed Scopus CINAHL Google Scholar