UnitedHealth Group's Optum division announced a new venture Monday that will aim to improve the "back office" functions of the health care system — the billing of patients and insurance companies so that doctors and hospitals can get paid.

The new company, known as Optum360, is a partnership with San Francisco-based hospital system Dignity Health, and will market software and support services that aim to make the process simpler for patients and more efficient for clinicians and administrators.

Dignity Health, the nation's fifth-largest health care system, operates 300 hospitals, urgent care centers, primary care clinics and home health services in 21 states. The nonprofit is recognized as one of the leaders in revenue cycle management.

Optum, based in Eden Prairie, is a fast-growing division of UnitedHealth that specializes in health IT and other technology services. The two organizations have worked together in the past, but this is their first solo business venture, according to an Optum official.

The launch of Optum360 comes as health care reform is shaking up the way hospitals and health care systems have traditionally been paid. The changes are also affecting the computerized bookkeeping process, which needs to be more flexible to adapt to new payment models as well as prepare for implementation of a new billing code system that is set to go into effect a year from now.

Optum360 will sell itself as a way to help hospitals make the transition from the current fee-for-service payment model, where doctors got paid for every treatment, toward "bundled payments," where insurers and hospitals agree on one fee for a range of services in a medical event, such as a knee replacement.

The companies said Optum­360 also will help hospitals and clinics offer patients a more streamlined admission process, which includes a simpler explanation of what is covered by insurance plus the ability to access information online and through mobile devices. And those hard-to-read claims statements will be easier to understand and its costs more transparent, officials said.

"Optum360 is singularly focused on helping care providers nationwide transform the registration, billing and payment system so it works better for them and their patients," Optum CEO Larry Renfro said in a statement.

The new company will arise out of the current work forces of both Optum and Dignity, employing about 3,000 workers, including 1,300 from Optum's staff spread across many states.

Optum360 already is working with additional "major health care provider partners," which will be announced in coming months, according to the announcement.

Jackie Crosby • 612-673-7335