These questions generate great feelings of angst in some and smug superiority in others. The truth is always in the middle.
FWIW here is a direct summary from the late, great Dr. Carl Bogardus who's as close to an authority on this matter as anyone in radiation oncology:
1. The radiation oncology physician is responsible for the overall care and maintenance of the health and safety of his/her patients as long as they are receiving radiation treatment. This responsibility may be delegated to another physician.
2. The radiation oncology physician may, from time to time, need to be absent from the facility while patients are receiving treatment. During this absence he/she may designate another physician [M.D., or D.O.] to provide medical coverage in his/her absence.
3. The covering physician is not required to be a radiation oncologist.
4. The covering physician should meet the criteria of a facility's limited privileges document.
5. In a hospital setting this covering physician does not necessarily need to be physically located within the radiation oncology department, but only has to be immediately available and able to render care and assistance when needed.
6. The covering physician may perform all E/M type procedures such as new patient evaluation, under beam evaluation [to include supervision of daily treatment and review of portal imaging], and follow-up evaluation.
7. The covering physician, unless he/she is a trained radiation oncology physician would not be expected to perform or supervise other radiation oncology specific procedures such as treatment planning, simulation, or dosimetry.
8. If the radiation oncology physician expects to be absent for four or more consecutive days, it is recommended that physician coverage be provided by a physician with training in the specialty of radiation oncology.
When a physician is providing direct supervision, he/she doesn't even need to know he/she is actually providing that supervision.
In a previous case, a judge found "...that under the incident to rules, in a physician-directed clinic the supervising physician need not be aware of every instance of service she is deemed to be supervising as long as she was physically present in the office suite and available for immediate assistance."
