Evidence-Based Medicine

• Defined by Dr. David Sackett in 1992 as: “the conscientious, explicit, and judicious use of the current best evidence in making decisions about the care of individual patients.”
• Means: “integrating individual clinical expertise with the best available external evidence from systematic research.”
• This definition has been refined as "the integration of best research evidence with clinical expertise and patient values" to achieve optimal clinical outcomes.
• Evidence-based practice (EBP) involves complex and conscientious decision-making which is based not only on the available evidence but also on patient characteristics, situations, and preferences.
• It recognizes that care is individualized and ever-changing and involves uncertainties and probabilities.

EBP vs EBM

Evidence-Based Practice (EBP) is an umbrella term that covers evidence-based medicine, evidence-based nursing, evidence-based public health, evidence-based dentistry, etc. Each specialty, however, may have its own approach to implementation.

"Three-Legged Stool" of EBP Definition

EBP is the integration of clinical expertise, patient values, and the best research evidence into the decision-making process for patient care.

1. Clinical expertise refers to the clinician’s cumulated experience, education, and clinical skills.
2. The patient brings to the encounter his or her own personal preferences and unique concerns, expectations, and values.
3. The best research evidence is usually found in clinically relevant research that has been conducted using sound methodology (Sackett D, 2002).

Evidence-Based Healthcare

Evidence-Based Healthcare is the conscientious use of current best evidence in making decisions about the care of individual patients or the delivery of health services.

Current best evidence here is up-to-date information from relevant, valid research about the effect of different forms of healthcare, the potential for harm from exposure to particular agents, the accuracy of diagnostic tests, and the predictive power of prognostic factors.

To Practice EBM,

• Be conscientious: It requires effort and thought.
• Be explicit: Decisions have to be backed up by good evidence.
• Relate it to specific problems: It is not about a hypothetical ‘average case’.
• Integrate individual clinical experience: It does not denigrate clinical skills in history taking, examination, and diagnosis.
• Look for current best evidence: Make an effort to search for the best current research evidence.

• Patients may be exposed to useless or dangerous treatments.
• Wastage of resources.
• Not applying the best and most effective treatment.

• It improves confidence in decision-making, making it easier to justify decisions to patients and managers and to communicate with other professions.
• It provides rules and rationale for group-based problem-solving and teaching.
• Means that good research findings are applied more quickly to clinical practice; for example, it took 10-15 years before trials proving the effectiveness of thrombolysis after MI were widely practiced.
• It can help interpret 'grey' indeterminate or intermediate results of clinical tests.
• Like Audit, EBM emphasizes outcomes (the end result for the patient) as well as process (what was done by healthcare professionals).
• EBM can be used to involve patients in decision-making.
• It fits in with the purchaser-provider split, as purchasers may insist on good evidence that a service or procedure has been proven to be effective before they place a contract for it.

• Finding and evaluating the evidence is time-consuming.
• Not everyone is skilled in locating information and using the computer.
• Resources are needed to acquire and maintain the databases.
• It is a rigorous and rigid system that tends to restrict those delivering care to patients.
• Poor indexing may lead to frustration or futile search.
• The 'Gold standard' Randomized Controlled Trial (RCT) was not intended to answer questions about the treatment of individual patients.
• It requires knowledge of statistics that only a few have mastered.

1. Asking a clinical question
2. Searching for the best evidence
3. Critically appraising the evidence
4. Integrating the evidence with one’s clinical expertise and patient preferences and values
5. Evaluating the outcomes of practice decisions or changes based on evidence

1. Type I Evidence: Provided by one or more well-designed randomized controlled clinical trial(s) (RCT) for therapeutic interventions or by one or more well-designed descriptive studies that address sensitivity, specificity, and predictive value (for diagnostic procedures/devices).
2. Type II Evidence: Provided by one or more well-designed observational studies, such as a case-control or cohort study, or a well-designed prospective case series, or clinically relevant basic science studies that address sensitivity, specificity, and predictive value.
3. Type III Evidence: Provided by studies not meeting the criteria of Type I or II, that may include expert opinion, field practitioner consensus, or other sources, as judged by an Expert Panel.

For the purpose of this document, “well designed” refers to a study that has, at a minimum, relatively high internal validity (low systematic error) and sufficient precision for statistical significance (adequate study numbers).

• CINAHL Complete (EBSCO)
• MEDLINE
• Cochrane Library (Wiley)
• National Guideline Clearinghouse
• Natural Standard