@article{walter2001-11410097,
  author  = {Walter, L. C. and Brand, R. J. and Counsell, SR. and Palmer, R. M. and Landefeld, C. S. and Fortinsky, R. H. and Covinsky, K. E.},
  title   = {{Development and validation of a prognostic index for 1-year mortality in older adults after hospitalization}},
  journal = {JAMA},
  year    = {2001},
  doi     = {10.1001/jama.285.23.2987},
  pmid    = {11410097},
  url     = {https://doi.org/10.1001/jama.285.23.2987}
}