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Dental Hygiene: Evidence Based Practice: EBP

EBP, Statistics tab, Journal Links

The American Dental Association and EBD

The American Dental Association (ADA) Center for Evidence Based Dentistry (EBD) offers tutorials that can be accessed by clicking on the graphic below:

Defining EBP

Evidence-Based Practice (EBP) is the framework for your clinical decision-making process. It is the integration of

  • your knowledge, skills, and past experience (Clinical Expertise);
  • the unique preferences, concerns and expectations of your patient (Patient Characteristics); and
  • valid and clinically relevant research (Best Evidence).



Types of Clinical Questions

Therapy - What is the treatment for a disease?

Diagnosis - power of a test to differentiate between those with and without a disease?

Prognosis - a patient’s likely course over time due to factors other than interventions?

Etiology/Harm - effects of potentially harmful agents on the patient?

5 A's - Steps for Acquiring Information


               - Review the Situation (Assess)

             - Define the clinical problem as a question (Ask)

             - Select resources, design a strategy, and search for the

               answer (Acquire)

             - Summarize the evidence yield (Appraise)

             - Apply the evidence (Apply)

Levels of Evidence

The level of evidence can be defined by the type of question. Levels of evidence for a "Therapy" question are different from the levels of evidence for an "Etiology" question. Please review the following from The Centre for Evidence-Based Medicine at Oxford:

Pyramid infographic from:

Level Description
Levels of Evidence in Nursing Research
I Evidence from a systematic review or meta-analysis of all relevant RCTs (randomized controlled trial) or evidence-based clinical practice guidelines based on systematic reviews of RCTs or three or more RCTs of good quality that have similar results.
II Evidence obtained from at least one well-designed RCT (e.g. large multi-site RCT).

Evidence obtained from well-designed controlled trials without randomization (i.e. quasi-experimental).

IV Evidence from well-designed case-control or cohort studies.
V Evidence from systematic reviews of descriptive and qualitative studies (meta-synthesis).
VI Evidence from a single descriptive or qualitative study.

Evidence from the opinion of authorities and/or reports of expert committees.

The table above is based on the following: Ackley, B. J., Swan, B. A., Ladwig, G., & Tucker, S. (2008). Evidence-based nursing care guidelines: Medical-surgical interventions. (p. 7)St. Louis, MO: Mosby Elsevier.

Study Design


Type of Question Suggested Best Type of Study
Therapy RCT > prospective cohort
Diagnosis Prospective, blind comparison to a 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