1. Department of Radiation Oncology, Mayo Clinic Rochester Minnesota USA
2. Department of Radiation Oncology, Hillman Cancer Center University of Pittsburgh Medical Center Pittsburgh Pennsylvania USA
3. Department of Statistics, Mayo Clinic Rochester Minnesota USA
4. Mayo Clinic, Department of Radiation Oncology, Mayo Clinic, Jacksonville Florida USA
5. Department of Radiation Oncology, Mayo Clinic Phoenix Arizona USA
6. Allegheny Health Networks Pittsburgh Pennsylvania USA
7. Medical Affairs, Varian Medical Systems Pittsburgh Pennsylvania USA
8. Department of Radiation Oncology, Cleveland Clinic Cleveland Ohio USA