2021 Updating and Validating the U.S. Veterans Affairs Frailty Index: Transitioning From ICD-9 to ICD-10. David Cheng†, Clark DuMontier†, Cenk Yildirim, Brian Charest, Chelsea E. Hawley, Min Zhuo, Julie M. Paik, Enzo Yaksic, J. Michael Gaziano, Nhan Do, Mary Brophy, Kelly Cho, Dae H. Kim, Jane A. Driver, Nathanael R. Fillmore‡, Ariela R. Orkaby‡† Equal first authorship · ‡ Equal senior authorship Journals of Gerontology: Series A76(7), 1318-1325 U.S. Veterans and VA Data Electronic Health Records Frailty Electronic Frailty Index ICD-10 Coding