Presented “An alternative method for assessing the fragility of survival analysis results” at the ASA Biopharmaceutical Section Regulatory–Industry Statistics Workshop.
Presented “Unlocking Multi-Institutional Insights into Disease Progression Using Federated Learning on Longitudinal Electronic Health Records” at JSM 2026.
PEAL, a lossless one-shot federated learning method for studying disease progression across institutions, published in npj Digital Medicine.
Presented “Federated Learning Algorithms with EHR Data: Generating Clinical Evidence from Multi-site Real-world Longitudinal Data” at the 2026 ICSA Applied Statistics Symposium.
Presented “Advancing Timely and Reliable Evidence Synthesis in Rapidly Evolving Research Areas through the Inclusion of Preprints” at ENAR 2026.
Presented “Advancing Timely and Reliable Evidence Synthesis in Rapidly Evolving Research Areas through the Inclusion of Preprints” at CFE-CMStatistics 2025.
Presented “Statistical Innovations Using Real World Data for Health System Performance Assessment with Perspectives on AI” at the 2025 IQVIA Institute Research Forum.
Presented “Unlocking Efficiency in Real-world Collaborative Studies: A Multi-site International Study with COLA-GLMM” at the 2025 IMS New Researchers Conference.
Joined the Johns Hopkins Data Science and AI Institute as a faculty member.
Affiliated appointment in the Division of Biomedical Informatics and Data Science, JHU School of Medicine.
Presented “Unlocking Efficiency in Real-world Collaborative Studies: A Multi-site International Study with COLA-GLMM” at ENAR 2025.
Presented “Statistical Innovations Using Real World Data for Health System Performance Assessment” at “Unlocking Insights from Electronic Health Record Data with Statistics and AI” at Brown University.
Presented “A One-shot and Lossless Federated Generalized Linear Mixed Effect Model” at the 2024 OHDSI Global Symposium.
Yong Chen*, Jiayi Tong*, Yiwen Lu*, Rui Duan, Chongliang Luo, Marc A. Suchard, Patrick B. Ryan, Andrew E. Williams, John H. Holmes, Jason H. Moore, Hua Xu, Yun Lu, Raymond J. Carroll, Scott L. Zeger, George Hripcsak, Martijn J. Schuemie
Journal of the American Medical Informatics Association (JAMIA), 2026
Sets out 10 best-practice principles for multi-site studies that use privacy-preserving distributed algorithms (PDA), from study preparation and protocol development to analysis and reporting.
Trial design–aware funnel plots that mark the decision boundaries of noninferiority and equivalence trials, to assess publication bias and inverse publication bias in meta-analyses.
Yicheng Shen, Ji Soo Kim, Chongliang Luo, Scott L. Zeger, Robyn T. Domsic, Ami A. Shah, Jiayi Tong
npj Digital Medicine, 2026
PEAL fits multi-level mixed-effects models with spline trends from a single round of summary statistics, matching pooled-data results; applied to systemic sclerosis cohorts at two centers.
A fragility index for survival data that counts the fewest changes in event or censoring status needed to overturn the statistical significance of a randomized trial result.
Jiayi Tong, Yifei Sun, Rebecca A. Hubbard, M. Elle Saine, Hua Xu, Xu Zuo, Lifeng Lin, Chunhua Weng, Christopher H. Schmid, Stephen E. Kimmel, Craig A. Umscheid, Adam Cuker, Yong Chen
Journal of the American Medical Informatics Association (JAMIA), 2025
A two-stage method for including preprints in meta-analyses: weight them by a confidence score, then adjust for publication or reporting bias; shown on two COVID-19 treatments.
Xing Xing, Lifeng Lin, Mohammad Hassan Murad, Jiayi Tong
Cochrane Evidence Synthesis and Methods, 2025
Tests GPT-4o and Llama 3.2 Vision on detecting publication bias from funnel plots in simulated meta-analyses; neither model detected it consistently without fine-tuning.
Clarifies how the term "weighted mean difference" relates to the mean difference, why it persists, and recommends clearer reporting in evidence synthesis.
Yiwen Lu*, Jiayi Tong*, Dazheng Zhang*, Jiajie Chen, Lu Li, Yuqing Lei, Ting Zhou, Leyna V. Aragon, Michael J. Becich, Saul Blecker, Nathan J. Blum, Dimitri A. Christakis, Mady Hornig, Maxwell M. Hornig-Rohan, Ravi Jhaveri, W. Schuyler Jones, Amber Brown Keebler, Kelly Kelleher, Susan Kim, Abu Saleh Mohammad Mosa, Kathleen Pajer, Jonathan Platt, Hayden T. Schwenk, Bradley W. Taylor, Levon H. Utidjian, David A. Williams, Raghuram Prasad, Josephine Elia, Christopher B. Forrest, Yong Chen
Nature Communications, 2025
In EHR data from 25 RECOVER institutions, children and youths with SARS-CoV-2 infection had higher risks of neuropsychiatric conditions, including anxiety, than matched COVID-19-negative peers.
Jiayi Tong, Jenna M. Reps, Chongliang Luo, Yiwen Lu, Lu Li, Juan Manuel Ramirez-Anguita, Milou T. Brand, Scott L. DuVall, Thomas Falconer, Alex Mayer Fuentes, Xing He, Michael E. Matheny, Miguel A. Mayer, Bhavnisha K. Patel, Katherine R. Simon, Marc A. Suchard, Guojun Tang, Benjamin Viernes, Ross D. Williams, Mui van Zandt, Fei Wang, Jiang Bian, Jiayu Zhou, David A. Asch, Yong Chen
npj Digital Medicine, 2025
COLA-GLMM fits generalized linear mixed models across sites in one communication round without loss of accuracy; validated on eight international databases for COVID-19 mortality risk factors.
Jiayi Tong*, Jie Hu*, George Hripcsak, Yang Ning, Yong Chen
Journal of Machine Learning Research, 2025
A distributed algorithm for average treatment effects in high-dimensional multi-site data that accounts for covariate shift across sites and approximates the pooled estimator.
Jiayi Tong*, Lu Li*, Jenna Marie Reps, Vitaly Lorman, Naimin Jing, Mackenzie Edmondson, Xiwei Lou, Ravi Jhaveri, Kelly J. Kelleher, Nathan M. Pajor, Christopher B. Forrest, Jiang Bian, Haitao Chu, Yong Chen
Statistics in Medicine, 2024
ODAP-B, a one-shot distributed algorithm for relative risks of rare binary outcomes, gives less biased estimates than two-step meta-analysis, shown with data from eight medical centers.
Eileen T. Lake, Bingyu Zhang, Jiayi Tong, Gloria Mpundu, Kelsey N. Gross, Malini H. Correa, Lauren B. Wethman, Lynne Moronski, Domenique Villani, Yong Chen
Nursing & Health Sciences, 2024
A meta-analysis of 160 publications from 38 countries that provides international benchmark values for the Practice Environment Scale of the Nursing Work Index.
Xiaohan Wang*, Jiayi Tong*, Sida Peng, Yong Chen, Yang Ning
Stat, 2024
A communication-efficient estimator of the average treatment effect for multi-site data, even when covariates outnumber patients at each site, that approximates the pooled estimator at a fast rate.
Yiwen Lu*, Jiayi Tong*, Jessica Chubak, Thomas Lumley, Rebecca A. Hubbard, Hua Xu, Yong Chen
Journal of Biomedical Informatics, 2024
Combines several error-prone EHR phenotypes with a small validated sample to reduce bias from phenotyping error, improving efficiency by up to 30% over using a single phenotype.
Jiayi Tong, Yishan Shen, Alice Xu, Xing He, Chongliang Luo, Mackenzie Edmondson, Dazheng Zhang, Yiwen Lu, Chao Yan, Ruowang Li, Lianne Siegel, Lichao Sun, Elizabeth A. Shenkman, Sally C. Morton, Bradley A. Malin, Jiang Bian, David A. Asch, Yong Chen
Journal of the American Medical Informatics Association (JAMIA), 2024
A federated framework with counterfactual modeling that assesses how site of care contributes to racial disparities in kidney graft failure across 73 U.S. transplant centers.
Jiayi Tong, Chongliang Luo, Yifei Sun, Rui Duan, M. Elle Saine, Lifeng Lin, Yifan Peng, Yiwen Lu, Anchita Batra, Anni Pan, Olivia Wang, Ruowang Li, Arielle Marks-Anglin, Yuchen Yang, Xu Zuo, Yulun Liu, Jiang Bian, Stephen E. Kimmel, Keith Hamilton, Adam Cuker, Rebecca A. Hubbard, Hua Xu, Yong Chen
Journal of the American Medical Informatics Association (JAMIA), 2024
A data-driven "confidence score," estimated with a survival cure model, for weighting preprints in systematic reviews and meta-analyses; validated on 146 COVID-19 therapeutics preprints.
Qiong Wu*, Jiayi Tong*, Bingyu Zhang, Dazheng Zhang, Jiajie Chen, Yuqing Lei, Yiwen Lu, Yudong Wang, Lu Li, Yishan Shen, Jie Xu, L. Charles Bailey, Jiang Bian, Dimitri A. Christakis, Megan L. Fitzgerald, Kathryn Hirabayashi, Ravi Jhaveri, Alka Khaitan, Tianchen Lyu, Suchitra Rao, Hanieh Razzaghi, Hayden T. Schwenk, Fei Wang, Margot I. Gage Witvliet, Eric J. Tchetgen Tchetgen, Jeffrey S. Morris, Christopher B. Forrest, Yong Chen
Annals of Internal Medicine, 2024
Estimates the real-world effectiveness of the BNT162b2 vaccine against infection and severe disease in children and adolescents in PEDSnet during the Delta and Omicron periods.
Jiayi Tong, Rui Duan, Ruowang Li, Chongliang Luo, Jason H. Moore, Jingsan Zhu, Gary D. Foster, Kevin G. Volpp, William S. Yancy Jr., Pamela A. Shaw, Yong Chen
Scientific Reports, 2023
A framework to detect self-reported weights that are missing not at random and correct the resulting bias, applied to the Keep It Off trial of financial incentives for weight-loss maintenance.
Mia Djulbegovic, Jiayi Tong, Alice Xu, Joanna Yang, Yong Chen, Adam Cuker, Allyson M. Pishko
Blood Advances, 2023
A meta-analysis of trials and observational studies on adding caplacizumab for immune TTP: faster response and fewer refractory cases, with more bleeding in randomized trials.
Jiayi Tong, Chongliang Luo, Md Nazmul Islam, Natalie E. Sheils, John Buresh, Mackenzie Edmondson, Peter A. Merkel, Ebbing Lautenbach, Rui Duan, Yong Chen
npj Digital Medicine, 2022
dCLR, a one-round distributed conditional logistic regression that accounts for between-site heterogeneity, applied to 14,215 COVID-19 patients from 230 clinical sites.
Journal of the American Medical Informatics Association (JAMIA), 2022
An outcome-dependent sampling design that uses EHR-derived phenotypes to choose which charts to review, making validation more efficient than sampling charts uniformly.
Jiayi Tong*, Zhaoyi Chen*, Rui Duan*, Wei-Hsuan Lo-Ciganic, Tianchen Lyu, Cui Tao, Peter A. Merkel, Henry R. Kranzler, Jiang Bian, Yong Chen
American Medical Informatics Association (AMIA) Annual Symposium Proceedings, 2020
Applies the one-shot distributed algorithm ODAL to OneFlorida data to identify risk factors for opioid use disorder, with better estimates than meta-analysis.
Jiayi Tong, Jing Huang, Jessica Chubak, Xuan Wang, Jason H. Moore, Rebecca A. Hubbard, Yong Chen
Journal of the American Medical Informatics Association (JAMIA), 2020
An augmented estimator that combines a small chart-reviewed sample with error-prone EHR phenotypes, reducing bias in risk-factor associations while keeping variance low.
Jiayi Tong*, Rui Duan*, Ruowang Li, Martijn J. Schuemie, Jason H. Moore, Yong Chen
Pacific Symposium on Biocomputing (PSB), 2020
A privacy-preserving, communication-efficient distributed algorithm that accounts for heterogeneous sites, outperforming ODAL and meta-analysis on OHDSI claims data.
Thita Chiasakul, Elizabeth De Jesus, Jiayi Tong, Yong Chen, Mark Crowther, David Garcia, Chatree Chai-Adisaksopha, Steven R. Messé, Adam Cuker
Journal of the American Heart Association, 2019
A meta-analysis of 68 studies finding that adults with arterial ischemic stroke more often carry inherited thrombophilias such as factor V Leiden and protein C or S deficiency.
Jiayi Tong*, Jing Huang*, Jingcheng Du, Yi Cai, Cui Tao, Yong Chen
American Medical Informatics Association (AMIA) Annual Symposium Proceedings, 2018
Uses a likelihood ratio test on VAERS reports to identify rare adverse events with year-varying reporting rates for the quadrivalent FLU4 influenza vaccine.
2017Department Honors in Mathematics (Applied) with High Distinction at University of California, San Diego
2017Honor society Phi Beta Kappa at University of California, San Diego
2015–2017Provost’s Honors at University of California, San Diego
Teaching
Instructor, 140.669: Leveraging Electronic Health Records (EHR) Data: Opportunities and Challenges for Evidence Generation, Johns Hopkins Bloomberg School of Public Health, Summer 2025, 2026
Instructor, 140.850: Introduction to Statistical Analysis and Evidence Generation with Electronic Health Records (EHR) Data, Johns Hopkins Bloomberg School of Public Health, Spring 2025, 2026