Only 6 percent of Minnesotans treated for depression at primary care clinics report that they're free of symptoms within six months, according to a new report by MN Community Measurement, a health-care quality group.

But an innovative treatment program known as "Diamond" was able to boost the success rate to 26 percent, the organization found in a report to be released Friday.

The Diamond program, which started in 2008, relies on "care managers" to maintain frequent contact with patients diagnosed with depression.

"We knew improving depression care was a very difficult task," said Jim Chase, president of MN Community Measurement, which tracks quality measures at medical clinics statewide. "We're now starting to see that clinics that implement changes ... have better outcomes."

As part of the Diamond project, clinic employees check on patients by phone to see if they're taking their medications or experiencing side effects, and offer coaching on how to cope with their symptoms. It started as a pilot project at 10 Minnesota clinics and has since spread to 83 clinics statewide.

The report found that patients enrolled in the Diamond program were much more likely to report that they were no longer depressed, or had less severe symptoms, than other patients six months after starting treatment.

The best results were at Mayo's Northwest Clinic in Rochester, which reported a six-month success rate of 36 percent.

"We have story after story of patients that say, 'Why don't we do this for all chronic illnesses?' " said Dr. Mark Williams, the lead psychiatrist for the Diamond project at the Mayo Clinic.

Clinics are rated on how many patients, after treatment, score in the normal range on a nine-point questionnaire known as the PHQ-9, which asks about depression symptoms such as trouble sleeping and feelings of hopelessness.

Williams said the questionnaire is a good, if imperfect measure of depression, and helps doctors track whether their patients are improving.

He noted that many primary care doctors struggle to treat patients with depression, and the Diamond project was designed to help them do a better job.

It's well known that depressed people can give up on treatment easily if left to their own initiative. With Diamond, "we are the people tracking them down," Williams said, and that has paid off in better outcomes. "We've had people say, 'I didn't know that I could feel this good.' "

As part of the project, several insurance companies have agreed to pay an extra monthly fee to the clinics to cover the costs. But so far, the federal Medicare program has refused to pay, which has limited the program's enrollment, said Nancy Jaeckels, vice president of the Institute for Clinical Systems Improvement, which launched the Diamond project in Minnesota.

Still, she said the program has proven its worth in multiple research studies, and now in practice across Minnesota.

Among patients who stuck with the program for six months, the results were even higher: 45 percent were free of depression symptoms and another 16 percent reported significant improvement. About 42 percent of the 3,037 Diamond patients could not be reached six months later and were presumed still to be depressed, Chase said, even though some of them probably recovered as well.

One reason the general success rate is so low -- 5.8 percent statewide -- is that many depressed patients are lost to follow-up because they don't return to their doctors, said Chase.

"We know some of those patients are not coming back because they're better," he said. "We know the majority of them aren't. That's how the system has, I think, failed in the past."

The key to the Diamond project, he said, is that patients are more likely to stay in treatment. "We've been trying to show there are ways to redesign the care to give better results."

To see the clinic scores, go to www.mnhealthscores.org.

For a list of Diamond clinics, go to www.icsi.org.

Maura Lerner • 612-673-7384