ANUPAM B. JENA, MD, PhD, is an economist, physician, and the Joseph P. Newhouse Professor at Harvard. Jena hosts the Freakonomics, MD podcast, which explores the hidden side of health care. CHRISTOPHER M. WORSHAM, MD, MPH, is a researcher, pulmonologist, and critical care physician at Harvard. Jena and Worsham practice medicine at Massachusetts General Hospital. Their research and writing have been published by the New England Journal of Medicine, JAMA, New York Times, Wall Street Journal, and Washington Post.