Six Valley health care systems join forces. (Arizona Health Care Alliance)

A new venture formed by six health care systems is expected to provide stiff competition for the Samaritan Health System, the largest such entity in the state.

Called the Arizona Healthcare Alliance, the venture was established to offer new contracting opportunities for third-party payors, including health-maintenance and preferred-provider organizations, as well as employers throughout the Valley.

The new venture involves Baptist Hospitals and Health Systems in Phoenix, including Arrowhead Community Hospital and Medical Center in the northwest Valley; Chandler Regional Hospital in the southeast Valley; John C. Lincoln Hospital and Health Center in North Phoenix; Lutheran Healthcare Network in the East Valley, which includes Mesa Lutheran and Valley Lutheran hospitals; PMH Health Resources Inc. in the south and west areas of the Valley; and St. Joseph's downtown.

The advantage to businesses will be more flexibility in choosing health care services for their employees, as well as the potential for saving money. Previously, …