Research interests include: Bayesian analysis, causal analysis, health services research, comparative effectiveness, environmental biostatistics, source apportionment, environmental intervention studies, principal stratification, spline regression. Specialities include: R statistical software, SAS, LaTeX, Knitr
Service (selected)
American Statistical Association, Mid-Tennessee Chapter: Treasurer, 2021 - present
useR!2022 Organizing Committee, 2021 - 2022
Biostatistics Graduate Program Admissions Committee, 2016 - present
Biostatistics Staff Professional Development and Promotions Committee, 2017 - present (chair, 2018 - 2022)
Biostatistics Summer Internships for Undergraduates Program: Reviewer, 2021, 2022; Professional Development Seminar Presenter, 2024
Biostatistics Faculty Search Committee, 2024
Mentoring
Geoffrey Fleming Academy for Excellence in Education Mentorship Program, 2021 - 2023 (inaugural cohort)
MS students
Xiangyu Ji, 2019 - 2021. Now Senior Biostatistician at Vanderbilt University Medical Center.
Cara Lwin, 2021 - 2024. Now Biostatistician at Vanderbilt University Medical Center.
PhD students
Alexis Fleming (oral exam committee), 2022 - present
Valerie Welty (dissertation committee), 2016 - 2023
Yeji Ko (dissertation committee), 2021 - present
Publications (selected)
Griffin KE, Snyder K, Javid AH, Hackstadt A, Greevy R, Grijalva CG, Roumie CL. Use of SGLT2i Versus DPP-4i as an Add-on Therapy and the Risk of PAD-Related Surgical Events (Amputation, Stent Placement, or Vascular Surgery): A Cohort Study in Veterans With Diabetes. Diabetes Care. 2025 Mar 1;48(3):361-370. doi: 10.2337/dc24-1546. PMID: 39977627; PMCID: PMC11870292.
Hackstadt AJ, Elasy TA, Gangaputra S, Harper KJ, Mayberry LS, Nelson LA, Peterson NB, Rosenbloom ST, Yu Z, Martinez W. Effects of a Patient Portal Intervention to Address Diabetes Care Gaps: Protocol for a Pragmatic Randomized Controlled Trial. JMIR Res Protoc. 2024-06-28; 13:e56123.
Chu PY, Hackstadt AJ, Chipman J*, Griffin MR, Hung AM, Greevy RA Jr, Grijalva CG, Elasy T, Roumie CL. Hospitalization for Lactic Acidosis Among Patients With Reduced Kidney Function Treated With Metformin or Sulfonylureas. Diabetes Care. 2020 Jul;43(7):1462-1470. doi: 10.2337/dc19-2391. Epub 2020 Apr 23. PMID: 32327421; PMCID: PMC7305006.
Roumie CL, Chipman J*, Min JY, Hackstadt AJ, Hung AM, Greevy RA Jr, Grijalva CG, Elasy T, Griffin MR. Association of Treatment With Metformin vs Sulfonylurea With Major Adverse Cardiovascular Events Among Patients With Diabetes and Reduced Kidney Function. JAMA. 2019 Sep 24;322(12):1167-1177. doi: 10.1001/jama.2019.13206. PMID: 31536102; PMCID: PMC6753652. Winner of the Patrick G. Arbogast Collaborative Publication Award.
Hackstadt AJ, Hess AM. Filtering for increased power for microarray data analysis. BMC Bioinformatics. 2009 Jan 8;10:11. doi: 10.1186/1471-2105-10-11. PMID: 19133141; PMCID: PMC2661050.
Italics denote Vanderbilt Biostatistics faculty and staff. Asterisks denote Vanderbilt Biostatistics students.