Abstract
Gatekeeper training programs are essential in equipping school teachers with the necessary skills to identify and respond to suicide risk. However, understanding how suicide literacy evolves over time remains limited, which hinders the effective tailoring of interventions. This study aims to identify developmental patterns in suicide literacy to optimize prevention efforts. The analysis utilizes data from a large-scale school-based randomized controlled trial conducted from December 2022 to March 2024, involving 84 schools randomly assigned to an intervention or waitlist control group. A total of 2,051 school teachers (74.9% female; mean age = 37.15 ± 8.84 years) from the intervention group were included, with assessments conducted at baseline (T1), immediately after training (T2), and at 6 months (T3) and 12 months (T4) follow-up. Latent class growth modeling was employed to identify distinct subphenotype trajectories of literacy development, while multinomial logistic regression examined baseline characteristics associated with these trajectories. Cross-lagged panel network analysis was used to explore the dynamic relationships between the components of the training over time. Four distinct literacy trajectory groups were identified: Dip–Recovery (9.60%), Stable–Low (10.68%), Growth–Stable (66.65%), and Peak–Decline (13.07%). The Growth–Stable group showed the most consistent literacy gains, the lowest stigmatization, and the highest levels of perceived competence, willingness to intervene, and gatekeeper behaviors. In the networks of this group, misconceptions about discussing suicide and silence were identified as key factors in sustaining long-term literacy retention. Literacies related to the prevalence and dynamic nature of suicidal ideation were among the most influenced beliefs. This study identifies distinct literacy subphenotype trajectories and the most influential knowledge affecting long-term retention. It highlights the need for tailored, ongoing reinforcement in gatekeeper training to ensure sustained literacy and effective suicide prevention strategies, particularly in reinforcing key literacy components to foster a proactive, informed response to suicide prevention.