aMayo Clinic College of Medicine, Rochester, MN
bDepartment of Emergency Medicine, Rochester, MN
cDivision of Biostatistics, Rochester, MN
dDepartment of Emergency Medicine, Mayo Clinic, Rochester, MN
Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article, that might create any potential conflict of interest. The authors have stated that no such relationships exist. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statement.