The objective of this study was to assess thecosts of a housing and case management program in a novel sample-homeless adults with chronic medical illnesses.

The study used data from multiple sources: (1) electronic medical records for hospital, emergency room, and ambulatory medical and mental health visits; (2) institutional and regional databases for days in respite centers, jails, or prisons; and (3) interviews for days in nursing homes, shelters, substance abuse treatment centers, and case manager visits. Total costs were estimated using unit costs for each service.

Compared to usual care, the intervention group generated an average annual cost savings of (-)$6,307 per person (95 percent CI: -16,616, 4,002; p = .23). Subgroup analyses of chronically homeless and those with HIV showed higher per person, annual cost savings of (-)$9,809 and (-)$6,622, respectively. Results were robust to sensitivity analysis using unit costs.

The findings of this comprehensive, comparative cost analyses demonstrated an important average annual savings, though in this underpowered study these savings did not achieve statistical significance.