Assessing the Reliability of Electronic Dental Records Through Agreement of Probing Pocket Depths Measured Between Two Closely Conducted Periodontal Exams
Apr 2025–present
Aya Mitani, Hanlong Chen, Yuning Wang, Christopher McCulloch
Dalla Lana School of Public Health, University of Toronto · Advisor: Dr. Aya Mitani
Agreement of probing pocket depths between two closely conducted periodontal exams, modelled with cumulative link mixed models with multi-level random effects and summarized by integral-based agreement and kappa statistics with delta-method variance.
Submitted to the Journal of Clinical Periodontology
Dynamic Prediction of Tooth Loss Using Landmarking Models with Clustered Survival Data
Jan 2025–present
Hanlong Chen, Xinyang Feng, Aya Mitani
Master’s thesis · Dalla Lana School of Public Health, University of Toronto · Advisor: Dr. Aya Mitani
A shared-frailty landmark framework with hierarchical Gaussian-process longitudinal smoothing for dynamic risk prediction in clustered survival data, together with a cluster-aware AUC algorithm and large-scale simulations on the Trillium HPC cluster.
Thesis defended · manuscript pending submission
Continuous Cognitive Heterogeneity in Dementia: A Severity Factor and an Age-Related Amnestic Axis Without Reproducible Subtypes
Oct 2024–present
Hanlong Chen∗,†, Ian Zhang∗, …, Malcolm Binns
Rotman Research Institute, Baycrest · Supervisor: Dr. Malcolm Binns
Whether the cognitive profiles of people living with dementia form reproducible discrete subtypes. Under cross-validated joint selection of PCA dimensionality and cluster number, the data point instead to a continuous severity factor and an age-related amnestic axis, with no subtype solution that replicates.
Manuscript in progress
Redundancy-Aware Model Assessment for Component and Cluster Selection in Clinical Subtype Discovery
Oct 2024–present
Ian Zhang∗,†, Hanlong Chen∗, …, Malcolm Binns
Rotman Research Institute, Baycrest · Supervisor: Dr. Malcolm Binns
Manuscript in progress
A Sequential Mixed-Effects Imputation Framework for Visit-Level Informative Missingness and Imputation-Aware Evaluation of Metabolic Subtyping Methods in Longitudinal EHR Data
Apr 2025–present
Hanlong Chen, Bruce Liu, Aya Mitani, Karim Keshavjee, Felipe Cepeda, Aziz Guergachi, Camellia Zakaria
Canadian Primary Care Sentinel Surveillance Network (CPCSSN) · Supervisors: Dr. Camellia Zakaria and Dr. Aya Mitani
A sequential mixed-effects imputation framework for visit-level informative missingness in longitudinal laboratory data, with an imputation-aware evaluation of how metabolic subtyping methods behave once the missingness is accounted for.
Manuscript in progress
Bayesian Modeling of Inverse Gaussian Outcomes
Sep 2023–May 2024
Department of Statistical Sciences, University of Toronto · Advisor: Dr. Murari Singh
Jeffreys and GIG-based priors for the coefficient of variation, with Gibbs sampling in OpenBUGS and R.
Undergraduate research project · completed
COVID-19 Epidemiologic Data Analysis
Summers 2021 & 2023
Guangzhou Center for Disease Control and Prevention
Surveillance data cleaning and analysis of vaccination impact for outbreak response.
Completed