Several of Nashville’s best-known health care leaders will help lead an effort to improve interoperability in medical technology systems. Milton Johnson, chairman and CEO of HCA Holdings Inc.; Wayne Smith, president and CEO of Community Health Systems; William Carpenter III, chairman and CEO of LifePoint Hospitals; Dr. Jeffrey Balser, vice chancellor for health affairs and dean of the Vanderbilt University School of Medicine; and Dr. Michael Schatzlein, CEO of Saint Thomas Health and a market leader for St. Louis-based Ascension Health, have been named to the board of directors of the Center for Medical Interoperability. They’re part of a 14-member board which includes representatives from other leading medical systems.