Firearm injury among people experiencing homelessness: Cross-sectional evidence from a national survey of United States emergency departments.

Objectives: Persons experiencing homelessness (PEH) are at high risk for violent victimization. This study leverages unique data from a national study in the United States of America to provide estimates of non-fatal firearm injury among PEH and to describe the contexts related to injury, such as substance use, intent of the injury, and precipitating interpersonal factors. Study design: Cross-sectional. Methods: Data from the 1993-2020 National Electronic Injury Surveillance System-Firearm Injury Surveillance Study (NEISS-FISS) were used to describe the context and characteristics of non-fatal firearm injury among PEH aged 16 years or older. Homeless status and substance use data were extracted from a de-identified narrative field. Estimates were weighted to account for the NEISS-FISS complex sampling design. Results: Probable homelessness was identified in 0.10% of cases (n = 3,225). Substance use was documented in 22.73% of cases. Assault comprised 82.64% of injuries. Patients were mostly male (81.38%). Missing data were common on contextual variables: verbal argument (64.62%), physical fight (54.48%) or other criminal activity (62.33%). Conclusions: Assault is a leading cause of non-fatal firearm injury for PEH and is greater than rates of assault in non-fatal firearm injuries in the general population. Substance use was documented in nearly one quarter of patients, although this is less than expected given prior evidence. Reliance on narrative fields for key variables likely underestimates rates of PEH and substance use.