Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research.
Sackett DL, Rosenberg WM, Gray JA, Haynes RB, Richardson WS. Evidence based medicine: what it is and what it isn't. BMJ. 1996;312(7023):71–72. doi:10.1136/bmj.312.7023.71
In essence Dr. Sackett said to use your clinical expertise or judgement, find the best evidence you can to support it, then incorporate your patient’s values and preferences.
Where these 3 concepts work together, you have evidence-based medicine.
The EBM pyramid outlines the levels of evidence in research literature. The pyramid is meant to visualize both the quality of evidence and the amount of evidence available. For example, systematic reviews are at the top of the pyramid, meaning they are both the highest level of evidence and the least common. As you go down the pyramid, the amount of studies will increase as the quality of the evidence decreases.