Abstract
The development and implementation of national suicide prevention strategies (NSPSs) is one policy response to suicide prevention adopted by the World Health Organization (WHO); however, evidence on their effectiveness remains limited and mixed. This study assessed the impact of implementing an NSPS on sex-specific suicide mortality rates in nine countries within the Region of the Americas from 2000 to 2021. Suicide rates were obtained from the WHO Global Health Estimates, and countries with an NSPS and the year it was first implemented were identified using the WHO MiNDbank. A comparative interrupted time-series analysis using linear mixed-effects models was conducted to estimate the effect of NSPS implementation on suicide mortality. The implementation of an NSPS was associated with a gradual and sustained decrease in suicide mortality rates: 3.00% per year among males (95% CI: -5.28%, -0.66%) and 2.55% per year among females (95% CI: -4.62%, -0.44%). No significant difference in effect was observed between sexes. These findings demonstrate an association between NSPS and reduced suicide mortality in countries within the region, emphasizing the value of their ongoing development and implementation. Although the association did not vary by sex, NSPS design should account for sex-specific epidemiological contexts.