A Los Angeles County experiment in housing some of the most medically ill homeless people in the region has shown early signs that it's cost-effective.

A study out Tuesday from the RAND Corporation found that the Housing for Health program has cut county expenses related to emergency medical services mental health care, substance abuse, and criminal justice for participants by about 60 percent. Balancing that out with the costs of housing and case management services, costs fell about 20 percent overall, researchers found.

The study followed the first 890 participants in the program and looked at their costs associatied with six county departments for 12 months before and 12 months after joining the program.

"So those findings are pretty compelling to suggest that providing supportive housing is going to save the county money as opposed to cycling in and out of emergency rooms and jail, which is what this population was doing," said Sarah Hunter, a senior behavioral scientist at the RAND Corporation.

The program takes frequent users of the county's health system who are homeless and puts them in permanent supportive housing, with the hopes of improving their conditions and saving county dollars. RAND's study is good news for advocates.

There are some caveats, however, Hunter said.

Researchers were not given information on how much the county spent on temporary housing while individuals awaited permanent placement, which could change the equation towards the costly. On the other side of the scale, they also did not evaluate cost savings to other county agencies that engage with the homeless population.

Overall, RAND recommended further research on the program.

Housing for Health, first piloted in 2012, has since housed over 3,400 people, as of the last quarterly report in June.