1 Center for Care Delivery and Outcomes Research, Minneapolis Veterans Affairs Health Care System, Minneapolis, MN.
2 Leonard Schanfield Research Institute, CJE SeniorLife, Chicago, IL; Department of Physical Therapy and Human Movement Sciences, Northwestern University, Feinberg School of Medicine, Chicago, IL.
3 Leonard Schanfield Research Institute, CJE SeniorLife, Chicago, IL.
4 Division of Geriatrics, Department of Internal Medicine, Yale School of Medicine, New Haven, CT.