Casebeer et al. BMC Medical Education 2010, 10:42 http://www.biomedcentral.com/1472-6920/10/42 Open Access RESEARCH ARTICLE © 2010 Casebeer et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Research article Evidence-based choices of physicians: a comparative analysis of physicians participating in Internet CME and non-participants Linda Casebeer* 1 , Jennifer Brown 2 , Nancy Roepke 1 , Cyndi Grimes 2 , Blake Henson 1 , Ryan Palmore 1 , U Shanette Granstaff 1 and Gregory D Salinas 1 Abstract Background: The amount of medical education offered through the Internet continues to increase, providing unprecedented access for physicians nationwide. However, the process of evaluating these activities is ongoing. This study is a continuation of an earlier report that found online continuing medical education (CME) to be highly effective in making evidence-based decisions. Methods: To determine the effectiveness of 114 Internet CME activities, case vignette-based surveys were administered to U.S.-practicing physicians immediately following participation, and to a representative control group of non-participants. Survey responses were analyzed based on evidence presented in the content of CME activities. An effect size for each activity was calculated using Cohen's d to determine the amount of difference between the two groups in the likelihood of making evidence-based clinical decisions. Results: In a sample of 17,142 U.S. physicians, of the more than 350,000 physicians who participated in 114 activities, the average effect size was 0.82. This indicates an increased likelihood of 48% that physicians participating in online activities were making clinical choices based on evidence. Conclusion: Physicians who participated in online CME activities continue to be more likely to make evidence-based clinical choices than non-participants in response to clinical case vignettes. Background Continuing medical education (CME) activities provide opportunities for medical practitioners to keep up with new information affecting the delivery of medical care, and ongoing participation is required by most physician state licensing boards [1,2]. Participation in CME or other medical education activities is also required by the licens- ing boards for other types of healthcare providers, such as physician assistants and nurse practitioners. CME pro- viders sponsor a variety of activities, such as courses, reg- ularly scheduled series, or enduring materials, defined as instructional materials that can be accessed at a time cho- sen by the participant. The number of hours of Internet-based enduring mate- rials provided by Accreditation Council for CME (ACCME)-accredited providers increased dramatically in recent years, from 16,802 hours in 2002 to 57,944 hours in 2008 [3,4]. This three-fold increase was accompanied by an even larger increase in the number of participants choosing Internet-based enduring materials; the number of physician participants increased from 305,410 individ- uals in 2002 to 4,365,014, nearly a ten-fold increase. Given the increasing number of CME activities offered on the Internet, and the even larger growth of participa- tion in these activities, assessing the effectiveness of Internet-based CME is crucial. Reviews of studies com- paring results from online and traditional CME materials conclude that Internet-based CME was as effective as the traditional CME delivery formats [5,6]. A recent review analyzed data pooled from published comparisons of par- ticipating in Internet-based CME activities vs. traditional CME activities and comparisons of participating in Inter- net-based CME activities vs. not participating in CME * Correspondence: linda.casebeer@ceoutcomes.com 1 CE Outcomes, LLC, 107 Frankfurt Circle, Birmingham, AL, 35211, USA Full list of author information is available at the end of the article