Policy on Evidence-Based Dentistry
IntroductionThe American Dental Association (ADA) has a long history of identifying and supporting scientific advances in dentistry. During the 20th century, the ADA emerged as the leading dental organization in the world, and, by 1930, established rigorous guidelines for testing and advertising of dental products. The Association, through the Council on Scientific Affairs' Seal of Acceptance Program, continues to provide practitioners and consumers with information on safe, effective dental materials, devices and therapeutic agents. The Council's actions are based upon available scientific evidence and are subject to reconsideration at any time that significant new evidence becomes available. The Association also relies on available scientific evidence in its commitment to using credible scientific data and analyses in policymaking, and its communications with the dental profession and the public.
During the 1990s, a new process for reviewing scientific evidence emerged in medicine and other health fields that relies on systematic approaches to summarize the large volume of literature that health care providers need to assimilate into their practices. Since health care providers do not have the time to read the thousands of articles published each year, the "evidence-based medicine" (EBM) process uses a systematic approach to review and publish the evidence relevant to specific clinical questions.
The goal of the EBM process is to help practitioners provide the best care for their patients. This process uses clinical and methodological experts to synthesize all of the evidence relative to a defined "question of interest."
This information from systematic reviews is then made available to practitioners for integration with their clinical experience and other factors relevant to specific patient needs and preferences. This characteristic of the EBM process is clearly explained in the classical definition of evidence-based medicine as "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, et al). Simply stated, evidence-based medicine is "the integration of the best research evidence with clinical expertise and patient values" (Sackett et al. Evidence-based Medicine. New York: Churchill Livingstone; 2000). Though this process was originally developed in medicine, its principles apply to all health care fields, including dentistry.
Definition of Evidence-based DentistryThe American Dental Association defines the term "evidence-based dentistry" as follows:
In adopting this definition for EBD, the American Dental Association recognizes that treatment recommendations should be determined for each patient by his or her dentist, and that patient preferences should be considered in all decisions. Dentist experience and other circumstances, such as patients' characteristics, should also be considered in treatment planning. EBD does not provide a "cookbook" that dentists must follow, nor does it establish a standard of care. The EBD process must not be used to interfere in the dentist/patient relationship, nor is it to be used solely as a cost-containment tool by third-party payers.
Evidence-based dentistry (EBD) is an approach to oral health care that requires the judicious integration of systematic assessments of clinically relevant scientific evidence, relating to the patient's oral and medical condition and history, with the dentist's clinical expertise and the patient's treatment needs and preferences.
Elements of the EBD Process
The EBD process is not a rigid methodological evaluation of scientific evidence that dictates what practitioners should or should not do. Rather, the EBD process is based on integrating the scientific basis for clinical care, using thorough, unbiased reviews and the best available scientific evidence at any one time, with clinical and patient factors to make the best possible decision(s) about appropriate health care for specific clinical circumstances. EBD relies on the role of individual professional judgment in this process.
The EBD process consists of four steps. The first step is to define a clinically relevant and focused question in the interest of finding the best available evidence to promote the oral health of patients. "Best evidence" is a term that refers to information obtained from randomized controlled clinical trials, non-randomized controlled clinical trials, cohort studies, case-control studies, crossover studies, cross-sectional studies, case studies, or the consensus opinion of experts in appropriate fields of research or clinical practice.
The second step focuses on systematically conducting searches for all studies and databases, published or unpublished, that may help to answer a clinically relevant question. After selecting, summarizing, and synthesizing all relevant studies that directly answer the focused clinical question, the strength of the available scientific evidence is graded using predefined criteria, and qualitative or quantitative analyses are conducted. Conclusions on the quality and strength of evidence are made, and gaps in the knowledge base that require further research are identified.
The third step of the EBD process is focused on translating the findings from systematic reviews for use by practitioners.
The final step of the EBD process involves assessing the health care outcomes following the findings of the previously outlined steps. This evaluation is conducted as part of the outcome assessment that health care providers integrate into their practices. This four-step process aims to help practitioners make the best-informed decisions with their patients.
The EBD process is time-consuming and thorough. The current approach in medicine and other health care fields is to rely on collaborative networks of experts in systematic review methods, statisticians, clinicians and funding agencies to conduct systematic reviews that can be used by professional associations or organizations. Currently there are collaborative research networks that conduct systematic reviews (e.g., the Cochrane Collaboration; Evidence-based Practice Centers (EPCs), funded by the U.S. Agency for Healthcare Research and Quality (AHRQ); and the University of York National Health Service (NHS) Centre for Reviews and Dissemination (CRD)). In the AHRQ-sponsored reviews, it is required that health care organizations (such as the ADA) play an active role in defining the questions for review and in evaluating the research findings. The ADA may elect to collaborate with these large networks of reviewers to conduct systematic reviews of clinically relevant questions.
The Role of the ADA in the EBD Process
The Association supports the concept of evidence-based dentistry developed through systematic examination of the best available scientific data, and will use this information to help shape the Association's Research Agenda. As such, the Association envisions developing clinical questions, setting protocols for systematic reviews, working with collaborative groups to conduct systematic reviews, critically appraising the reviews and policies developed by other organizations, and developing mechanisms for translating and disseminating information to the membership.
Glossary of Terms Relating to Evidence-based Dentistry1
This glossary is designed to assist dental professionals and public policymakers in developing a common language for discussion of issues pertaining to evidence-based dental care.
Best evidence is a term that refers to information obtained from randomized controlled clinical trials, non-randomized controlled clinical trials, cohort studies, case-control studies, crossover studies, cross-sectional studies, case studies or, in the absence of scientific evidence, the consensus opinion of experts in the appropriate fields of research or clinical practice. The strength of the evidence follows the order of the studies or opinions listed above.
Case-control study involves identifying subjects with a clinical condition (cases) and subjects free from the condition (controls), and investigating if the two groups have similar or different exposures to risk indicator(s) of factor(s) associated with the disease.
Case-series is a report on a series of patients with an outcome of interest. No control group is involved.
Clinical practice guideline (parameter of care) is a systematically developed statement designed to assist both practitioner and patient with decisions about appropriate health care for specific clinical circumstances.
Clinical protocol is a step-by-step decision-making tool that describes how a health condition is diagnosed and managed.
Cohort study involves identifying two groups (cohorts) of subjects, one that did receive the exposure of interest and another that did not, and following these cohorts forward for the outcome of interest.
Controlled clinical trial is a study that uses the same design features of a randomized controlled clinical trial (see definition below), but, for reasons beyond the control of the investigators, the subjects are assigned using a non-random process into control or experimental groups.
Crossover study design is the administration of two or more experimental therapies, one after the other in a specified or random order, to the same group of patients.
Cross-sectional study is the observation of a defined population at a single point in time or in a specified time interval. Exposure and outcome are determined simultaneously.
Evidence-based dentistry is an approach to oral health care that requires the judicious integration of systematic assessments of clinically relevant scientific evidence, relating to the patient's oral and medical condition and history, with the dentist's clinical expertise and the patient's treatment needs and preferences.
Evidence-based health care extends the application of the principles of evidence-based medicine (see below) to all professions associated with health care, including purchasing and management.
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.
Meta-analysis is a review that uses quantitative methods to combine the statistical measures from two or more studies and generates a weighted average of the effect of an intervention, degree of association between a risk factor and a disease, or accuracy of a diagnostic test.
Probability of success is a ratio of the number of patients who benefit from an intervention to all those who receive an intervention. A probability figure, such as 0.5 or 50%, means that out of 100 patients, 50 would benefit from an intervention and 50 would not benefit. Neither the dentist nor the patient can determine beforehand to which of the two groups a patient will belong.
Randomized controlled clinical trial is a study in which participants are randomly (i.e., by chance) assigned to either an experimental group or control group. The experimental group receives the new intervention and the control group receives a placebo or standard intervention. These groups are followed up for the outcomes of interest.
Systematic review is a process of systematically locating, appraising and synthesizing evidence from scientific studies in order to obtain a reliable overview. The aim is to ensure a review process that is comprehensive and unbiased. Findings from systematic reviews may be used for decision-making about research and the provision of health care.
1Some of the definitions are based on information provided in the glossary of the NHS Research and Development Centre for Evidence-based Medicine.
Page Updated: February 28, 2008
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