
Delta: HealthTech Innovators How AI Turns Messy EHR Into Clear Survival Predictions
Can AI forecast ICU risk from the first 36 hours of EHR data?
University of Washington researcher Sihan explains TrajSurv, a survival-prediction model that converts noisy, irregular ICU time series into interpretable latent trajectories using Neural Controlled Differential Equations (NCDEs) and time-aware contrastive learning aligned to SOFA. We cover how trajectories outperform snapshots, handle missingness without heavy imputation, and remain clinically legible via vector-field feature importance and trajectory clustering.
Validated on MIMIC-III and eICU with reported C-index ≈0.80 and cross-cohort ≈0.76, TrajSurv points to safer escalation, de-escalation, and bed allocation in the ICU.
In this episode: survival prediction basics; limits of Cox/RSF vs deep time-series models; NCDE explained in plain language; first-36h feature set (53 labs/vitals/demographics); metrics (C-index, Brier, dynamic AUC); interpretable clustering linked to outcomes; and what’s next—adding interventions for counterfactual simulation and extending to oncology.
Link to the paper: https://arxiv.org/abs/2508.00657
Timestamps
00:00 Why trajectories beat snapshots in EHR
01:00 Guest intro: Sihan, UW Biomedical Informatics
01:40 Survival prediction 101 and clinical use
03:40 From Cox/RSF to deep learning on time-varying data
05:03 What is TrajSurv (pronounced “traj-surf”)?
06:16 NCDE explained with the “ship + weather” analogy
08:14 Handling irregular sampling and missing data
09:14 Time-aware contrastive learning aligned to SOFA
10:47 Datasets: MIMIC-III and eICU; first 36h features (labs, vitals, demo)
12:40 Results: C-index ≈0.80; cross-cohort ≈0.76; interpretability
14:30 Workflow: CDS, monitoring, escalation, de-escalation
16:15 Why humans miss multi-variable long-horizon trends
18:21 Latent trajectory clustering and survival differences
23:18 Next: interventions, counterfactuals, oncology applications
25:40 Closing
Roupen Odabashian LinkedIn: https://www.linkedin.com/in/roupen-odabashian-md-frcpc-abim-183aaa142/
Sihang Zeng: https://www.linkedin.com/in/zengsh/
#HealthcareAI #ClinicalDecisionSupport #EHR #ICU #SurvivalAnalysis #DeepLearning #NCDE #MIMICIII #eICU #SOFA
