Employment of physician assistants, nurse midwives, clinical psychologists, or nurse practitioners, known collectively as physician extenders (PEs, mid-level providers, nonphysician practitioners, or limited license professionals), benefits a practice because while their “incident to” services can garner the same payments as physicians, PEs typically have salaries that are much lower than physicians. But there’s a Catch 22: This effective way to increase practice profitability is also one of the most effective ways to come under payor scrutiny.