Model-based Usability and Error Analysis of an Electronic Health Record Interface Scott D. Wood 1 , Dean F. Sittig 2 , Adol Esquivel 2 , Daniel Murphy 2 , Brian Reis 2 , Hardeep Singh 2 1 VA National Center for Patient Safety, Ann Arbor, MI 2 Houston VA HSR&D Center of Excellence, and The Center of Inquiry to Improve Outpatient Safety Through Effective Electronic Communication, both at the Michael E. DeBakey Veterans Affairs Medical Center and the Section of Health Services Research, Department of Medicine, Baylor College of Medicine, Houston, TX ABSTRACT Electronic health records, such as the VA’s Computerized Patient Record System (CPRS), have the potential to fundamentally improve many aspects of healthcare. Evaluating usability for such systems, however, remains challenging due to inherent system and task complexity. Similarly, testing system redesigns or augmentation is perhaps more challenging, not only due to interdependence and tight coupling between system components, but also due to factors such as patient safety and privacy. The notification system within CPRS is one such tightly-coupled component that permits healthcare providers to receive patient-specific alerts and reports from other members of a patient’s healthcare team. We propose the use o f human performance modeling to help quantify usability issues with notification processing, to better understand how the current user interface affects patient safety, and to help develop and test alternative designs. Keywords: Electronic Health Records, EHRs, Usability, Cognitive Modeling