Dr. Catherine MacLean is Chief Value Medical Officer at the Hospital for Special Surgery and a member of the American College of Physicians Performance Measurement Committee. Stephen Morrissey, the interviewer, is the Managing Editor of the Journal. C.H. MacLean, E.A. Kerr, and A. Qaseem. Time Out - Charting a Path for Improving Performance Measurement. N Engl J Med 2018;