Thirty-two groups were named Monday to test a new health-care model, called for in the health-care law and designed to improve care for seniors while reducing costs.

The groups, which range from Boston-based Partners HealthCare, the largest health-care provider in Massachusetts, to the doctor-led HealthCare Partners of southern Nevada, were selected as the first Medicare accountable care organizations by the Department of Health and Human Services.

The organizations are designed to save $1 billion over five years by promoting coordination between doctors and hospitals and ensuring that people with chronic conditions such as diabetes or high blood pressure get the care they need to stay out of the hospital.

While some lawmakers are calling for Medicare cuts, Health and Human Services Secretary Kathleen Sebelius said the so-called “pioneers” would boost the quality of care for seniors, even as they reduced costs by changing the incentives to reward doctors and hospitals for better outcomes. “Many of these organizations are finding that doing care the right way can bring down the cost,” she said.

The health-care law attempts to use the federal government’s role as payer for Medicare to set an example of paying for quality, rather than for the number of services provided, as is done now.

The 32 pioneers were selected from 80 applicants, officials said. All have made progress toward, or are already largely functioning as accountable-care organizations and will serve as a guide for the dozens of organizations expected to apply for a much larger program, called the Medicare Shared Savings Program, set to launch next year.

“It’s a wide cross-section of all kinds of organizations,” said Chas Roades, chief research officer with the Advisory Board Co., a research and consulting firm that counsels health-care organizations.

Roades, however, criticized a lack of geographic diversity. Six of the pioneers are in California, five are in Massachusetts and only one is in Florida, a state with a large elderly population.

The initiative to set up accountable-care organizations got off to a bumpy start this year. In March, major industry players were disappointed in draft rules that detailed how organizations would participate and be able to share in the expected cost savings. When applications for the test program came due in August, national leaders in providing integrated care, such as the Mayo Clinic and Geisinger Health System, passed on joining.

In October, however, the final set of rules was released, and many organizations seemed to regain confidence about participating.

As accountable-care organizations ramp up their efforts, patients can expect to see changes. Roades said that hospitals, primary-care providers and others will be communicating more explicitly and pursuing more intensive management of conditions.

“One of the biggest challenges,” he said, “is actually going to be engaging consumers in a different kind of health care: one that’s really active.”

This article was produced in collaboration with Kaiser Health News. KHN is an editorially independent program of the Henry J. Kaiser Family Foundation, a nonprofit, nonpartisan health-policy research and communication organization not affiliated with Kaiser Permanente.