Latent Similarity Gaussian Processes: A Theory-Grounded Approach to Personalized Suicide-Risk Forecasting for Clinical Decision-Support
This study addresses the challenge that high patient heterogeneity and the low base rate of suicide events constrain the accuracy of personalized risk prediction. To overcome this, we propose a latent similarity Gaussian process that embeds patients into a continuous latent space to jointly model inter-patient similarity and individual risk trajectories. Specifically, an identifiable dual-channel similarity kernel is designed to selectively leverage peer information, while a correction mechanism is introduced to mitigate model degeneration induced by mean-field variational inference. Evaluated on dense longitudinal data, the proposed approach significantly outperforms population-level, individual-level, and hierarchical baselines. Notably, it substantially improves predictive precision for first-time suicide events, thereby establishing a novel paradigm for individualized risk assessment in clinical settings.