Expert Opinion Handbooks
5-Evidence based medicine uses evidence to make clinical decisions. There is a hierarchal system for classification of evidence. This hierarchy is known as the levels of evidence. Physicians are encouraged to find the highest level of evidence to answer clinical questions (Barnes, Rohrich, & Chung, 2012, p. 305). The higher the level the more strength the evidence has. Randomized controlled trials (RCT’s) are the strongest research designs for treatment or intervention studies because they exert the most control over the methods and the results are considered more trustworthy (Thomas, 2017). It is important to note that a high level of evidence for a treatment study may not be the highest level of evidence for a study for prognosis. The strongest levels of evidence are at the top of the hierarchy. Some examples put concepts into practice from the different levels of evidence that may include practice alerts for revising current policies and instituting new practices.
Meta-Analysis A systematic review that uses quantitative methods to summarize the results.
Systematic Review An article in which the authors have systematically searched for, appraised, and summarized all the medical literature for a specific topic.
Critically Appraised Topic Authors of critically-appraised topics evaluate and synthesize multiple research studies.
Critically Appraised Articles Authors of critically-appraised individual articles evaluate and synopsize individual research studies.
Randomized Controlled Trials RCT’s include a randomized group of patients in an experimental group and a control group. These groups are followed up for the variables/outcomes of interest.
Cohort Study Identifies two groups (cohorts) of patients, one which did receive the exposure of interest, and one which did not, and following these cohorts forward for the outcome of interest.
Case-Control Study Involves identifying patients who have the outcome of interest (cases) and control patients without the same outcome and looking to see if they had the exposure of interest.
Background Information / Expert Opinion Handbooks, encyclopedias, and textbooks often provide a good foundation or introduction and often include generalized information about a condition. While background information presents a convenient summary, often it takes about three years for this type of literature to be published.
Animal Research / Lab Studies Information begins at the bottom of the pyramid: this is where ideas and laboratory
research takes place. Ideas turn into therapies and diagnostic tools, which then are tested with lab models and
References
Barnes, P. B., Rohrich, R. J., & Chung, K. C. (2012, July 1). The Levels of Evidence and their role in Evidence-Based Medicine. Plastic Reconstructive Surgery, 128(1), 305-310. https://doi.org/doi: [10.1097/PRS.0b013e318219c171]
Thomas, C. J. (2017, May 23). What Does “Levels of Evidence” Mean in Evidence-Based Practice? Nursing Education Expert. Retrieved from https://nursingeducation
