Introduction: Clinical trial data can be presented in ways that exaggerate treatment effectiveness. Physicians consider therapy more effective, and may be more likely to make inappropriate practice changes, when data are presented in relative terms such as relative risk reduction rather than in absolute terms such as absolute risk reduction and number needed to treat. Our purpose was to determine (1) how frequently continuing medical education (CME) speakers present research data in relative terms compared to absolute terms; (2) how knowledgeable CME speakers and learners are about these terms; and (3) how CME learners want these terms presented. Methods: Analysis of videotapes and PowerPoint slides of 26 CME presentations, questionnaire survey of CME speakers and learners, and focus groups with learners. Results: Speakers presented data more frequently in relative than absolute terms, but most frequently in general terms such as frequencies, percentages, graphs, and P-values with no data. Of 1367 PowerPoint slides, 269 presented research data, and of these, 225 (84%) presented data in general terms, 50 (19%) in relative terms and 19 (7%) in absolute terms. CME speakers understood relative and absolute terms better than learners. Approximately 25-35% of speakers and 45-65% of learners could not correctly calculate relative risk reduction, absolute risk reduction, and number needed to treat. Learners wished to have these terms presented in CME programs in a consistent and easily understood format and requested a brief review of them at the beginning of CME programs. Discussion: Presentation of research data in most CME programs is inadequate to allow learners to make fully informed therapeutic decisions. Speakers and learners need professional development to improve their presentation and understanding of research data. (Contains 2 tables and 1 figure.)