Jefferson City, Mo. ? Residents in rural Missouri tend to have access to fewer doctors than their counterparts in cities, and that could create problems as the new federal health care law is implemented, the Missouri Hospital Association said Thursday.

There is an average of one primary care physician for every 1,776 residents in rural areas, compared with an average of one doctor for every 962 residents in Missouri’s metropolitan areas, the hospital association said in a report. Those doctors also tend to be older in rural areas, with 62 percent being age 50 or older compared with 55 percent in metro areas.

The hospital association based its statistics on definitions used by the U.S. Census Bureau, which categorizes 35 of Missouri’s 114 counties and the city of St. Louis as metropolitan areas. Those metro areas include traditionally urban areas such as St. Louis County as well as some counties typically thought of as rural, such as Schuyler County in northern Missouri, which is considered part of the Kirksville area.

The hospital association said the figures show that rural residents could have more difficulty finding primary care physicians when a federal health care law expands Medicaid coverage, creates health-insurance exchanges for people to shop for policies and requires most people to have health insurance beginning in 2014.

“As health care reform increases access for those currently uninsured, there will be significant challenges to meet their needs in an area already strained by limited resources and services,” the hospital association said in its report.

Access to primary care physicians matters to hospitals because people sometimes rely on their emergency rooms instead of first going to doctors’ offices.