People with an employer-sponsored health plan tend to visit their primary care physician (PCPs) less than those people without, but those with work-sponsored insurance are more commonly seeing nurse practitioners and physician assistants than earlier this decade, according to a new Health Care Cost Institute report.

Per the report, researchers said they found an 18 percent decrease in PCP office visits between 2012 and 2016; however, there was a correlating 14 percent increase in office visits for all providers. All of this new data suggests that non-PCPs are seeing more patients than their PCP counterparts for their care.

Nurse practitioners and physicians assistants are taking on a larger role in primary care, then. They are helping "fill primary care gaps in the coming years" as physician shortages continue to cause industry concern.

But even this news is met with some skepticism from industry insiders. The reason why is related to varying state regulations throughout the U.S. For example, just 22 states allow nurse practitioners full authority to practice primary care independently while 16 states allow limited practice authority and 12 states require onsite physician supervision.

The new research shows that state laws influence geographic variation in office visits. Additionally, per the report, 51 percent of office visits for employer-sponsored insurance were for PCPs in 2012, but after just four years, there was a drop to well below the majority to 43 percent.

What signifies this is a trend is that every state experienced drops in PCP office visits for the duration of the report, from 2012 through 2016. Washington, D.C., saw a drop of 6 percent while there was a 31 percent drop in North Dakota.

Nurse practitioner and physician assistant office visits increased in every state, though, including a 37 percent increase in New Mexico to a 285 percent jump in Massachusetts. Office visits to nurse practitioners and physician assistants soared by as much as 129 percent between 2012 and 2016.

Factors that influenced these trends include state policies, insurance benefit design and access to providers. Another major factor may be cost.

Care provided by nurse practitioners and physician assistants is often cheaper (though not by much) than that provided by the more-schooled primary care physicians, but that perception may not be true. In fact, HCI found similar costs for office visits despite the education levels of those providing the care. PCP office visit costs were $106 in 2016 and $103 for NPs and PAs. In this case, perception is not reality.

Finally, the report did not explore how age or demographics influence the reported trends. Patients, especially younger ones, seek convenience and may not feel as connected to a specific PCP. Those patients are more likely to get care beyond a usual doctor's office visit.

According to reporting by Healthcare Dive, a UnitedHealth Group report found that 13 percent of Americans live in a county with a PCP shortage, a problem more common in rural areas. The divide will likely grow: Only one in six medical school graduates picked a primary care residency program last year, which means the gap is growing.