Here is a snippet from the incident to article on aafp.org (American Academy of Family Practitioners) On a side note: if there is a change in the plan of care, also, the service cannot be billed incident to. The patient would at that point have to be seen by the physician and not the NPP.
What?s covered?
When these nonphysician providers bill on their own provider numbers, Medicare will pay them to perform any service it would pay a physician to perform as long as they are acting within the scope of their state license. The claims are paid at 85 percent of the physician fee schedule directly to the physician or physician group employing the nonphysician provider. Services that may be billed on the nonphysician provider?s number include in-office services without physician supervision, inhospital services without physician involvement, nursing-home visits (except for the resident assessment, which can only be performed by a physician), house calls, consultations, the ordering and provision of diagnostic tests and time-based evaluation and management services where more than 50 percent of the service is counseling or coordination of care. Services performed by other nonphysician providers incident-to these nonphysician providers? services are also covered by Medicare if they would be covered were they incident-to a physician?s services.