Randomized controlled trials and consensus as a basis for interventions ininternal medicine

Objectives. To estimate the proportion of routine clinical interventions in internal medicine that are supported by the results of randomized controll ed trials or consensus amongst experienced internists. Design, Retrospective review of case records allowed one or more major diag nosis-intervention combination(s) to be identified for each patient. The sc ientific literature was searched for metaanalyses and randomized controlled trials in electronic databases that supported the specific intervention us ed. When support from randomized trials was lacking, possible consensus on management was sought by asking national expert panels of experienced clini cians. Setting. Department of Medicine at a Swedish teaching hospital. Subjects, At total of 197 consecutively admitted medical inpatients. Results, Fifty per cent of the diagnosis-intervention combinations (186/369 ) were supported by results from randomized controlled trial evidence and 3 4% (125/369) were supported by consensus amongst experienced clinicians. Th e proportion of interventions based on randomised controlled trials was hig hest in patients with cardiac (64%) and other circulatory diagnoses (73%). There were no important differences between sexes or between age groups. Conclusions. Half of the interventions used in routine clinical practice am ongst medical inpatients are supported by results from randomized controlle d trials. These results refute popular claims that only a small proportion of medical interventions are supported by scientific evidence.