Evidence Based Dentistry Hierachy of Evidence Systematic review

Evidence Based Dentistry

Hierachy of Evidence • • • Systematic review Randomised Control Trial Cohort Studies Case control studies Case series/ reports Editorials/ expert opinion

Definitions Systematic Review/ Metanalysis: A systematic review summarises the results of available carefully designed healthcare studies (controlled trials) and provides a high level of evidence on the effectiveness of healthcare interventions. Judgments may be made about the evidence and inform recommendations for healthcare. Randomised Control Trial: (RCT) A study in which people are allocated at random (by chance alone) to receive one of several clinical interventions. One of these interventions is the standard of comparison or control. The control may be a standard practice, a placebo ("sugar pill"), or no intervention at all. Cohort Study: A study design where one or more samples are followed prospectively and subsequent status evaluations with respect to a disease or outcome are conducted to determine which initial participants exposure characteristics (risk factors) are associated with it Case Control: A study that compares patients who have a disease or outcome of interest (cases) with patients who do not have the disease or outcome (controls), and looks back retrospectively to compare how frequently the exposure to a risk factor is present in each group to determine the relationship between the risk factor and the disease. Case control studies are observational because no intervention is attempted and no attempt is made to alter the course of the disease. The goal is to retrospectively determine the exposure to the risk factor of interest from each of the two groups of individuals: cases and controls. These studies are designed to estimate odds. Case Series: A case series is a type of medical research study that tracks subjects with a known exposure, such as patients who have received a similar treatment, or examines their medical records for exposure and outcome. Expert opinion

GDC ‘…explain, evaluate and apply the principles of an evidence based approach to learning, clinical and professional practice and decision making’ The American Dental Association ‘…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.

Processing Information 1. Question: form a question that needs to be answered that is based on the patient’s problem. 2. Retrieve: access available evidence. 3. Appraise: critically appraise the information accessed. 4. Apply: use the results found act on them to provide treatment in practice. 5. Evaluate: assess performance

Manual vs Electric Toothburshes- An example Question: form a question that needs to be answered that is based on the patient’s problem. 2. Retrieve: access available evidence. 3. Appraise: critically appraise the information accessed. 4. Apply: use the results found act on them to provide treatment in practice. 5. Evaluate: assess performance

Question Form a question that needs to be answered that is based on the patient’s problem. ‘is a powered toothbrush more effective than a manual toothbrush? ’

Retrieve What information is available? 1 Cochrane Review that accepted 56 papers

Appraise Trials were of varying bias Information was of moderate quality Short and Long term plaque removal improvement 6% decrease in gingivitis with the Löe index and a 11% reduction in the Silness index