Findings This quality improvement study of 55 354 to 451 837 individuals per month aged 13 years or older found that implementation of the Zero Suicide model was associated with a reduction in suicide attempt rates in 3 of 4 health systems, while the fourth system experienced a lower sustained rate. Two systems that implemented the model before the observation period maintained low or declining rates.
Meaning Findings from this study support implementation of the Zero Suicide model in outpatient mental health care.
Importance Suicide is a major public health concern, and as most individuals have contact with health care practitioners before suicide, health systems are essential for suicide prevention. The Zero Suicide (ZS) model is the recommended approach for suicide prevention in health systems, but more evidence is needed to support its widespread adoption.
Objective To examine suicide attempt rates associated with implementation of the ZS model in outpatient mental health care within 6 US health systems.
Design, Setting, and Participants This quality improvement study with an interrupted time series design used data collected from January 2012 through December 2019, from patients aged 13 years or older who received mental health care at outpatient mental health specialty settings within 6 US health systems located in 5 states: California, Oregon, Washington, Colorado, and Michigan. Analyses were conducted from January through December 2024.
Exposure The ZS model was implemented in 4 health systems at different points during the observation period (2012-2019) and compared with health systems that implemented the model before the observation period (postimplementation). Implementation included suicide risk screening, assessment, brief intervention (safety plan, means safety protocol), and behavioral health treatment.
Main Outcomes and Measures The primary outcome was a measure of standardized monthly suicide attempt rates captured using health system records and government mortality records. Suicide death rates were also measured as a secondary outcome.