[1] Mayo Clin, Dept Radiat Oncol, Rochester, MN USA
[2] Mayo Clin, Div Biomed Stat & Informat, Rochester, MN USA
[3] Mayo Clin, Dept Radiat Oncol, Phoenix, AZ USA
[4] Mayo Clin Arizona, Dept Radiat Oncol, Phoenix, AZ USA
[5] Mayo Clin, Dept Radiat Oncol, Jacksonville, FL 32224 USA