Design the search
Once you have clarified your clinical question, you need to identify relevant studies from a number of different sources (see Where to look for research evidence) that may be able to answer it.
Your search needs to identify:
Studies of an appropriate design to answer the question, whether it be systematic reviews of RCTs, RCTs, cohort studies, studies assessing adverse effects; see Search strategies for example search filters used to retrieve specific study types.
Studies assessing the relevant PICOT (Population, Intervention, Comparison, Outcome, and Time frame) to answer your clinical question; see Case study of a search.