Evidence-based practice is using evidence from medical research to inform clinical decisions.
Evidence, however, comes in different forms and some are considered more high quality than others. Take, for example, the following pyramid outlining the level of evidence:
Text source: Melnyk, B.M., & Fineout-Overholt, E. (2011). Evidence-based practice in nursing and healthcare: A guide to best practice. Philadelphia: Lippincott, Williams & Wilkins.
The bottom level, Background Information/Expert Opinion, is given the lowest ranking of quality of evidence. This is because background information is often used to get familiar with a topic but rarely is cited in an actual study. Expert opinion, in this case, does not have evidence to back it up.
The top level of the pyramid is Systematic Reviews. These reviews can take a few years to compile and comprehensively pull together all studies that have come before it to answer a clinical question.
The goals of your research informs what type of evidence might be most appropriate.
Systematic reviews can appear in any of our databases, but here are a few additional resources: