Fitting a routine health-care activity into a randomized trial: an experiment possible without informed consent?

Due to possible methodological and practical problems, many researchers refrain from using a randomized controlled trial design to evaluate procedures already embedded in routine health care. We performed a randomized controlled trial on the effects of routine individual feedback on test ordering behavior of family physicians. The trial started after 4 years of feedback and lasted for 2.5 years. With some adaptations a randomized trial proved to be possible. In evaluating health-care procedures that cannot be blinded in a traditional way, asking full and study-specific informed consent may conflict with the validity of the design. In such studies, an alternative procedure is to be considered. Our trial, with doctors as study subjects, was held on an already accepted routine procedure (feedback). This made it possible to refrain from obtaining study-specific informed consent. Consequently, a Hawthorne effect and contamination of the trial arms through information leakage could be avoided. Justification and general criteria for not obtaining full and study-specific informed consent are worked out. In health-care research on the performance of doctors or on interventions into the quality of care, obtaining a general informed consent in advance is an acceptable alternative approach.