1 The Johns Hopkins University Applied Physics Lab, Johns Hopkins University, Laurel, MD 20723, USA; Department of Neurology, The Johns Hopkins Hospital, Baltimore, MD, USA. Electronic address: adam.cohen@jhuapl.edu.
2 Department of Internal Medicine, Division of Gastroenterology, The Johns Hopkins Hospital, Baltimore, MD, USA; Armstrong Institute for Patient Safety and Quality, Baltimore, MD, USA.
3 Center for Health and Technology, University of Rochester Medical Center, Rochester, NY, USA.
4 Department of Internal Medicine, Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, MA, USA; Clinical and Quality Analysis, Information Systems, Partners Healthcare, Wellesley, MA, USA.
5 Department of Anesthesia, Massachusetts General Hospital, Boston, MA, USA.