“In a review conducted for the Institute of Medicine, Chad Boult and his colleagues at Johns Hopkins University identified 15 models of comprehensive care for older adults with chronic illness, which fit into six broad categories related to care settings.… Most models reduced hospital use or length of stay, although the evidence was mixed in some cases. Three models—interdisciplinary primary care for heart failure patients, transitional care from hospital to home, and ‘hospital-at-home’ programs that substitute care in the patient’s home in lieu of a hospital stay—showed some evidence of lower cost, although this was not directly measured in all studies.