“[N]ationwide, the majority of publicly insured children live within 15 minutes of a Medicaid dentist, and in some states it's as high as 99 percent," said Marko Vujicic, chief economist and vice president of the American Dental Association’s (ADA) Health Policy Institute (HPI). “Moreover, when it comes to why people avoid going to the dentist, not being able to find one is pretty far down the list.”

However, the data actually seem to be telling a different story, according to H. Milton Stewart School of Industrial and Systems Engineering (ISyE) Professor Nicoleta Serban. With a team of undergraduate and graduate students from ISyE, and using extensive data on the Medicaid population — data unavailable to the ADA — she found problems with the ADA’s results: “The estimates provided by HPI substantially overestimate access for children with public insurance. The overestimation comes from both data limitations and the shortcomings of the methodology employed.”

The ADA is considered by policymakers to be the source of data in support for dental health care-related policies and laws. If the organization decides there is no access problem, policymakers may be inclined not to pursue national and state policies to improve access for children on Medicaid.

Serban and her students developed a mathematical model for matching need/demand and supply for particular health care services under a series of realistic constraints. These constraints were specified by data about dentists who accept children with Medicaid, as well as how many of these patients the dentists have seen over the course of a year. Other factors include whether the children’s parents have a car, and the preference of parents to not have to travel too far to take their kids to a dentist.

Serban’s methodology uncovered an even more dismal state of affairs for children in the state of Georgia than portrayed by the ADA: 23 percent of children on Medicaid do not have access to dental care within the state access standards (30 miles for urban areas and 45 miles for rural areas). This is in significant contrast to the six percent estimate by the ADA. Additionally, Serban’s model found that in Georgia, 23.8 percent of children had a distance of five miles — or, equivalently, 15 minutes of travel time. In the city of Atlanta, the average travel time was considerably longer than 15 minutes.

“There are potentially major policy and practice implications to substantially overestimating spatial access to dental care,” noted Serban. “State policymakers may erroneously conclude that advancing policy to improve access to dental care for publicly insured children is not needed in their jurisdiction.”

Her research is ripe for substantive impact because many states are considering enacting bills that would grant more flexibility for providing and supporting basic dental care services by dental hygienists and therapists — providers who tend to work in rural areas and administer care to children on Medicaid. Moreover, local health departments also may use this research to receive funding to support programs addressing access barriers.

Serban’s research is building momentum among public health decision-makers, many of whom have reached out to her ISyE health analytics group to search for evidence to accurately portray the barriers parents face in finding a dentist who accepts Medicaid insurance. This is a multiyear endeavor, but Serban hopes that not too far in the future — and as a result of correctly interpreting the available data — all U.S. children will have access to basic dental care in their schools.