Research

Evidence-Based Medicine

Evidence-based medicine (EBM) combines the best current available evidence with clinical expertise and patient preference into the decision making process. EBM helps us to understand and interpret medical and surgical treatments, medical tests, and disease prognosis.

The evidence for EBM comes largely from clinical studies. Clinical studies about a specific intervention or treatment are assigned an evidence level based upon the type and quality of the study. These evidence levels (1 being the best, through 5) are then combined to arrive at an overall evidence grade. Grade A evidence shows that there is clear benefit to the treatment and should be strongly recommended for patients with similar diseases and characteristics.

Most surgical evidence is given a grade of B or C because it is either unfeasible or unethical to do studies that randomize patients between real surgery and fake surgery. Many surgical studies are done retrospectively, that is we look back in time to see which group of patients did best with the treatment that was offered to them.

Many physicians are working hard to improve the evidence base for surgical treatments, particularly in cancer treatments.