[1] Mayo Clin, Div Pulm & Crit Care Med, Rochester, MN 55905 USA
[2] Mayo Clin, Robert D & Patricia E Kern Ctr Sci Hlth Care Deli, Rochester, MN 55905 USA
[3] Mayo Clin, Knowledge & Evaluat Res Unit, Rochester, MN 55905 USA
[4] Mayo Clin, Evidence Based Practice Ctr, Rochester, MN USA
[5] Univ Washington, Harborview Med Ctr, Div Pulm Crit Care & Sleep Med, 325 9th Ave, Seattle, WA 98104 USA
[6] Univ Washington, Cambia Palliat Care Ctr Excellence, Seattle, WA 98195 USA
[7] Mayo Clin, Med Lib, Rochester, MN USA
[8] Mayo Clin, Dept Med, Rochester, MN USA