1. Department of Radiation Oncology University of Michigan Hospital and Health Systems Ann Arbor Michigan USA
2. Department of Radiation Oncology Washington University School of Medicine St. Louis Missouri USA
3. Department of Medical Physics Memorial Sloan‐Kettering Cancer Center New York New York USA
4. Department of Radiation Oncology University of Iowa Iowa City Iowa USA
5. Department of Radiation Oncology University of Florida Health Proton Therapy Institute Jacksonville Florida USA
6. Department of Radiation Oncology Medical College of Wisconsin Milwaukee Wisconsin USA
7. Department of Radiation Oncology Virginia Commonwealth University Richmond Virginia USA
8. Department of Imaging Physics The University of Texas MD Anderson Cancer Center Houston Texas USA
9. Department of Radiation Oncology Allegheny Health Network Cancer Institute Pittsburgh Pennsylvania USA
10. Department of Radiotherapy Medical University of Vienna, Vienna Austria USA
11. Department of Radiation Oncology Sidney Kimmel Cancer Center at Thomas Jefferson University Philadelphia Pennsylvania USA