1. Department of Geriatric Medicine/Gerontology; Ohio University Heritage College of Osteopathic Medicine (OU-HCOM); Athens; OH; USA
2. Center for Clinical Epidemiology and Biostatistics; University of Pennsylvania, School of Medicine; Philadelphia; PA; USA
3. Division of Epidemiology and Biostatistics, Department of Preventive Medicine and Biometrics; Uniformed Services University of the Health Sciences; Bethesda; MD; USA