2021-2022 Schedule


Friday, October 29, 2021
12:00 p.m. to 1:00 p.m.

Virtual Seminar
For Zoom details, please contact DINR

Dr. James O'Malley
Professor of Biostatistics at The Dartmouth Institute and the Department of Biomedical Data Science at the Geisel School of Medicine, Dartmouth College

Title: Optimal Physician Shared-Patient Networks and the Diffusion of Medical Technologies

Social network analysis has created a productive framework for the analysis of the histories of patient-physician interactions and physician collaboration. In this talk we use the data of "referral paths" --  sequences of patient-specific temporally linked physician visits -- culled from a large set of Medicare claims data in the United States to perform a five-factor experiment that produces 80 distinct projections of the bipartite patient-physician mixing matrix to a unipartite physician network, which is further analyzed at the level of the 2,219 hospitals in the final analytic sample. We summarize the networks of physicians within a given hospital using a range of directed and undirected network features. The different projections and their underlying factors are evaluated in terms of the heterogeneity of the network features. We also evaluate the projections relative to their ability to improve the predictive accuracy of a model estimating a hospital's adoption of implantable cardiac defibrillators, a novel cardiac intervention.

James O’Malley, Ph.D., is Professor in the Department of Biomedical Data Science and The Dartmouth Institute of Health Policy and Clinical Practice at the Geisel School of Medicine at Dartmouth. His methodological interests in statistics encompass social network analysis, multivariate hierarchical models, causal inference using instrumental variables, and Bayesian inference. Much of his work is motivated by problems in health policy and health services research. He has published over 220 peer-reviewed research papers and is an Associate Editor at the journals Statistics in Medicine and Observational Studies. He was chair of the Health Policy Statistics Section (HPSS) of the American Statistical Association (ASA) in 2008 and co-chaired its International Conference in 2011. In 2011 he received the HPSS Mid-career Excellence award, in 2012 was elected to be a fellow of the ASA, and in 2019 the ISPOR Methodological award for scientific excellence.