Health care systems in Minnesota have a unique history of setting aside competitive instincts to pursue common improvements in patient care, such as the “Safest in America” partnership a decade ago, when metro hospitals agreed on a technique to mark the sites of surgical incisions.

One can imagine the benefit of standardizing whether X marked the limb for an operation — or the limb to avoid!

But a joint venture by HealthPartners and Allina to improve care in the northwest metro has taken that spirit a step further.

Recognizing that the two health systems provided most of the primary care in the diverse and high-cost region, they formed the Northwest Metro Alliance in 2010 to identify weaknesses in health care that they could improve together. Five years later, the effort is paying off.

Coordinating care through four HealthPartners clinics along with Allina’s Mercy Hospital and five clinics, the providers sought to improve mental health care access, reduce unnecessary hospital readmissions, increase student health screenings, and improve adherence to prescription medications among chronically ill patients.

In a report to be released later this month, the alliance will show that costs for its privately insured patients increased less over the last two years than costs for Twin Cities patients overall. Among low-income patients with Medicaid coverage, spending was even lower than expected. A 2 percent decline in spending on these patients from 2013 to 2014 saved $7 million in public funding.

“While some were skeptical that we could effectively collaborate with a competitor, five years in we are seeing some extraordinary results,” Dr. Penny Wheeler, Allina’s president and chief executive, said in a memo.

The experiment also seems to be helping patients. Adding mental health practitioners in clinics and expanding day treatment at Mercy, for example, led to a 7 percent decline in hospitalizations for people in psychiatric crises.

Next up for the alliance is reducing waste and improving pain medicine in the region, which has seen a rash of deaths from prescription painkiller overdoses. A first step is the addition of the HealthPartners Riverway Clinic to provide more comprehensive pain management, including exercise, rehabilitation and education classes.