Final answer:
Ordering a chest X-ray without a medical condition indicating its need is not an example of medical necessity. X-ray photons carry more energy than visible light and can harm patients, which justifies concerns regarding unnecessary X-rays.
Step-by-step explanation:
Ordering a chest X-ray on all patients admitted to a facility is not an example of medical necessity. Medical necessity means that a medical service or test is ordered because it is considered necessary for the diagnosis or treatment of a patient's reported symptoms or medical condition. For instance, if a patient like John suggests having symptoms of influenza, after evaluating him with a stethoscope, it may be medically necessary for the physician to order a chest X-ray to rule out pneumonia or other complications.
In contrast to visible light, X-ray photons carry considerably more energy and hence have the potential to harm tissues and DNA, increasing the risk of cancer. This is why there is concern about overuse of X-rays, whereas sitting under the bright lights of a waiting room doesn't pose the same risk