Clinical practice guidelines (CPGs) often serve as the knowledge base for clinical decision support (CDS). While CPGs are rigorously created by medical professional societies, the concepts in each guideline may not be sufficient for translation into CDS applications. In addition, clinicians' perceptions of these concepts may differ greatly, affecting the implementation and impact of CDS within an organization. Five guidelines developed by the American College of Emergency Physicians were systematically explored, generating fifty-one unique clinical concepts. These concepts were presented to two nurses and two physicians, whom were asked to assess and comment on the capture of each clinical concept in the electronic health record (EHR) and the subsequent availability of the data for CDS. Nurses and physicians showed differing perceptions of data availability. These differing perceptions may influence an organizational approach to developing and implementing CDS, potentially informing our understanding of why CDS may not achieve the intended impact.