(HealthDay)—Primary care practices may be relying on advanced practitioners (APs) to accommodate new Medicaid beneficiaries following the passage of the Affordable Care Act, according to a study published in the July/August issue of the Annals of Family Medicine.

Lena Leszinsky and Molly Candon, Ph.D., from the University of Pennsylvania in Philadelphia, used data from a secret shopper study in which callers simulated new Medicaid patients and requested appointments with 3,742 randomly selected primary care practices in 10 states. Simulated patients asked whether the practitioner was a physician or an AP.

The researchers found that from 2012 through 2016, the proportion of primary care appointments scheduled with APs increased from 7.7 to 12.9 percent. At federally qualified health centers (FQHCs), the proportion of appointments scheduled with APs was 8.5 percentage points higher than that seen at non-FQHCs. There was no evidence that accountable care organizations or practices with more market power scheduled more appointments with APs. The proportion of AP appointments was lower in counties with a higher concentration of black and Hispanic residents and in counties with higher median incomes.

“Appointments with APs occurred more frequently in lower-income counties with a higher concentration of whites, suggesting that APs in primary care aren’t evenly distributed,” the authors write.