Definition of "Medically Necessary" used by Lucent:

Medically necessary: (medical necessity). The determination of medical necessity is made by the applicable health care company. Care is considered medically necessary if:

• It is accepted by the health care profession in the U.S. as appropriate and effective for the condition being treated,
• It is based upon recognized standards of the health care speciality involved,
• It represents the most appropriate level of care: the frequency of services, the duration of services, and the site of services, depending on the seriousness of the condition being treated (such as in the hospital or in the physician's office), and
• It is not experimental or investigational.

Or click here for a copy of the document as of 6/2002.