authors Keeney, T Flom, M Ding, J Sy, M Leung, K Dae Hyun Kim, MD, MPH, ScD Orav, J Vogeli, C Ritchie, C S
has subject area Academic Medical Centers Aged COVID-19 Delivery of Health Care Frail Elderly Frailty Health Expenditures Humans Medicare Retrospective Studies United States