NASHVILLE (AP) - Vanderbilt University Medical Center and Chattanooga's Erlanger Health System are joining forces.

They have signed a pair of agreements that bring Erlanger into a statewide network and open up future collaboration opportunities between the two academic medical institutions, officials say.

Under the network agreement, Erlanger will join the Vanderbilt Health Affiliated Network, which includes 56 hospitals, 35 clinics and nearly 4,000 doctors across Tennessee and into Kentucky, Arkansas, Virginia and Mississippi, news outlets reported Tuesday. Adding Erlanger fills a hole in the network in southeastern Tennessee.

The physician-led network hopes to cut health care costs while improving the quality of care, Erlanger President and CEO Kevin Spiegel said in a statement.

"We really do believe connectivity to all the patients and all the providers in the region is strategically important for us," Spiegel told The Tennessean (http://tnne.ws/29qPldW). "I think Vanderbilt has a jump on the nation because it's already bringing all of West Tennessee, Middle Tennessee and now East Tennessee in one network so we can meet and talk in a structured way about 'how do we improve population health in our state.'"

A collaborative agreement, also announced this week, will enable Erlanger and Vanderbilt, which normally compete for patients and doctors, to form new clinical programs and services.

The two institutions will work on collaborations around pediatric care, said Dr. C. Wright Pinson, CEO of Vanderbilt Health System, who expects some integration around trauma care. Erlanger, which has three helicopters in East Tennessee and two in Georgia, is a regional trauma destination that has not historically overlapped with VUMC.