Physicians expect a treatment to be more effective when its clinical outcomes aredescribed as relative rather than as absolute risk reductions. We examinedwhether effects of presentation method (relative vs. absolute risk reduction)remain when physicians are provided the baseline risk information, a vital pieceof statistical information omitted in previous studies. Using a between-subjectsdesign, ninety five physicians were presented the risk reduction associated witha fictitious treatment for hypertension either as an absolute risk reduction oras a relative risk reduction, with or without including baseline riskinformation. Physicians reported that the treatment would be more effective andthat they would be more willing to prescribe it when its risk reduction waspresented to them in relative rather than in absolute terms. The relative riskreduction was perceived as more effective than absolute risk reduction even whenthe baseline risk information was explicitly reported. We recommend thatinformation about absolute risk reduction be made available to physicians in thereporting of clinical outcomes. Moreover, health professionals should becognizant of the potential biasing effects of risk information presented inrelative risk terms.