ARE THERAPEUTIC DECISIONS SUPPORTED BY EVIDENCE FROM HEALTH-CARE RESEARCH

Background: One of the most common decisions physicians face is decidi ng which therapeutic intervention is the most appropriate for their pa tients. In recent years much emphasis has been placed on making clinic al decisions that are based on evidence from the medical literature. D espite the emphasis on incorporation of evidence-based medicine into t he undergraduate curriculum and postgraduate medical training programs , there has been controversy regarding the proportion of interventions that are supported by health care research. Objective: To investigate the proportion of major therapeutic interventions at our institution that are justified by published evidence. Methods: One hundred fifty c harts from the internal medicine department were reviewed retrospectiv ely. The main diagnosis, therapy provided, and patient profile were id entified and a literature search using MEDLINE was performed. A standa rdized search strategy was developed with high sensitivity and specifi city for identifying publication quality. The level of evidence to sup port each clinical decision was ranked according to a predetermined cl assification. In this system there were 6 distinct levels, which are e xplained in the study. Results: Of the decisions studied, 20.9% could be supported by placebo-controlled randomized trials and 43.9% by head -to-head trials. Half of these were shown to be significantly superior to the treatment against which it was being compared. For 10 of the 1 50 clinical decisions, evidence was found demonstrating alternative th erapies as being more effective than that selected. Conclusions: Most primary therapeutic clinical decisions in 3 general medicine services are supported by evidence from randomized controlled trials. This shou ld be reassuring to those who are concerned about the extent to which clinical medicine is based on empirical evidence. This finding has pot ential for quality assurance, as exemplified by the discovery that a l iterature search could have potentially improved these decisions in so me cases.