Joining Health Care and Homeless Data Systems Using Privacy-Preserving Record-Linkage Software

Homelessness dramatically reduces life expectancy and contributes to poor health outcomes directly (through exposure to the elements and violence) and indirectly (through poor management of chronic medical conditions).1,2The prevalence of chronic medical conditions that would benefit from primary medical care is high among people experiencing homelessness; however, emergency departments often function as the site of health care, resulting in fragmented care at the level of the institution or provider.3,4 Despite evidence demonstrating the beneficial effects of permanent housing with supportive services for some people experiencing homelessness,5 there is uncertainty regarding the long-term impact on health.6As many regions ofthe United States attempt to address the increasing number of people experiencing homelessness, housing advocates are eager to better understand the needs of potential clients and receive feedback on the impact of interventions on health services utilization, quality of life, and mortality. Additionally, there is a need to better estimate the number of people experiencing homelessness and to establish a system to prioritize limited housing based on factors such as chronicity of homelessness and vulnerability-a concept that often includes medical comorbidities.