TIP #1: SEED ARTICLE
Begin your research with a "seed article" - an article that strongly supports your research topic. Then use a citation database to follow the studies published by finding articles which have cited that article, either because they support it or because they disagree with it.
TIP #2: SNOWBALLING
Snowballing is the process where researchers will begin with a select number of articles they have identified relevant/strongly supports their topic and then search each articles' references reviewing the studies cited to determine if they are relevant to your research.
BONUS POINTS: This process also helps identify key highly cited authors within a topic to help establish the "experts" in the field.
According to the Centre for Evidence Based Medicine (CEBM), well-formed clinical questions are essential in practicing EBM. "To benefit patients and clinicians, such questions need to be both directly relevant to patients' problems and phrased in ways that direct your search to relevant and precise answers." - CEBM, University of Toronto, Asking Focused Questions
The PICO model is a tool that can help you formulate a good clinical question. Sometimes it's referred to as PICO-T, containing an optional 5th factor.
|P - Patient, Population, or Problem
|What are the most important characteristics of the patient? How would you describe a group of patients similar to yours?
|I - Intervention, Exposure, Prognostic Factor
|What main intervention, prognostic factor, or exposure are you considering? What do you want to do for the patient (prescribe a drug, order a test, etc.)?
|C - Comparison
|What is the main alternative to compare with the intervention?
|O - Outcome
|What do you hope to accomplish, measure, improve, or affect?
|T - Time Factor, Type of Study (optional)
Literature Reviews: An Overview for Graduate Students by North Carolina State University Libraries