Leadership & Staff

Antigone Kouvelis

She/Her

Program Administrator Senior

Antigone Kouvelis has worked in the fields of criminal justice and public health for over three decades. Before coming to Northwestern, she was employed by Lurie Children’s Hospital of Chicago since 2005 working on the Illinois Violent Death Reporting System (IVDRS) project. Her role consisted primarily of data collection in six Illinois counties. The project has grown to include eighty counties as abstraction sites, capturing more than 97% of violent deaths and unintentional overdoses in the state of Illinois. Her responsibilities currently include project management, data validation and cleaning, quality assurance, contributing to data analysis and dissemination, and establishing and maintaining relationships with data partners and advisory board members. She is also responsible for hiring, onboarding, and overseeing the work of the data abstractors team. She regularly fields questions and provides guidance regarding coding decisions. The IVDRS and SUDORS projects and team moved to Northwestern University’s Buehler Center as of February 2021. Previous employers include Lurie Children’s Hospital of Chicago, Chicago Department of Public Health, and Illinois Criminal Justice Information Authority.

Kathleen Kelly

She/Her

Program Coordinator Senior

Katie is one of our Community Outreach Coordinator. She earned her MPA from Rutgers University and loves the intersection of public policy and data analysis. Katie has been with us for over four years, working with Central and Southern Illinois counties to understand and apply our data. In her free time she loves to read and go on road trips with her whole family—her husband, three children and two dogs!

Karla J. Cervantes

She/Her

Data Assistant Associate

I’ve been at Northwestern with the IVDRS and SUDORS team for five years. It’s been a good experience thus far. I’ve learned a lot and alongside my fellow data abstractors, we’re able to ensure our project close out expectations are met. Cheers to more success!

Melissa A. Imburgia, MA

She/Her

Program Coordinator Senior/Center Administrator

Melissa Imburgia serves as the administrator for the Buehler Center. She handles the Center’s financial, HR, events, facilities, communications and administrative tasks. As a higher education administrator, she values the development and promotion of leadership and career development for students, staff and faculty. For any role, it is important for her to exercise a strong sense of emotional intelligence, compassion, and empathy in the workplace. The promotion of inclusive and progressive administrative practices are the main components of her professional goals and expectations.

Nia Jovan Andrews, MJ

She/Her

Communications Coordinator Senior

Nia Jovan Andrews is the Senior Communications Coordinator for the Illinois Violent Death Reporting System (IVDRS) and the State Unintentional Drug Overdose Reporting System (SUDORS) at Northwestern University. Since September 2020, she has led communication strategy, digital content, and public-facing dissemination efforts, translating complex surveillance data into accessible reports, data briefs, and visual materials for public health partners, policymakers, and the public. Her work focuses on clarity, ethical storytelling, and strengthening the connection between data and community impact.

Nyah I. Brown

She/Her

Data Assistant Associate

Nyah Brown is a Data Assistant Associate with the Buehler Center. I recently graduated from Case Western Reserve University with a BA in Medical Anthropology. I also have minors in Public Health and Spanish. As a Chicago native, I am thrilled to be supporting the IVDRS and SUDORS projects! Outside of work, I love weight lifting, cooking, and (constantly) trying new restaurants.

Oyindamola O. Ajala, MPH

She/Her

Research Data Analyst

Oyindamola O. Ajala is an Epidemiologist at Northwestern University, where she supports statewide public health surveillance and reporting efforts. Her work includes analysis, visualization, and mapping of complex health data for the Statewide Unintentional Drug Overdose Reporting System (SUDORS) and the Illinois Violent Death Reporting System (IVDRS), helping inform prevention strategies and data-driven decision-making. She holds a Master of Public Health (MPH) with a concentration in Epidemiology and is currently pursuing a Doctor of Public Health (DrPH) in Social Epidemiology at Mercer University. Her professional interests include applied epidemiology, health equity, injury, violence, and disease prevention, public policy, and the use of geospatial data to support public health action.

Samantha Z. Cervantes 

She/Her

Data Assistant Associate

Sarah B. Welch, MPH

She/Her

Clinical Research Associate

Sarah is an evaluator and researcher working in the public health and health services field since 2009. She is a methodologist with experience working on quantitative, qualitative and mixed-methods research and evaluation projects with academic and community colleagues. As the Director of Evaluation Research in the Buehler Center for Health Policy and Economics she provides high quality, state of the art evaluation services to Northwestern faculty, staff, and community organizations working on public health research, policy, and programming efforts. Ms. Welch has a strong background in community-engaged research and data collection with youth and families.  In addition to her evaluation and research project work, Sarah offers trainings and workshops with the intent of strengthening the evaluation and research capacity of those working to improve health in Chicago, the U.S., and internationally.

Sean Johnston

He/Him

Program Coordinator

Sean is the Program Coordinator for the Block-by-Block Initiative, seeking to utilize the Center's research and data to inform our boots on the ground partners in overdose prevention around the state since 2022. Sean is a passionate Harm Reductionist with 8 years of direct service work with Drug Checking and Syringe Service Programs in Minnesota and Illinois. When not at work you can find him ice climbing or hanging out at the sauna.  

Shivangi Sharma, MS

She/Her

Research Data Analyst Associate

Shivangi is a Data Scientist specializing in building scalable data pipelines, advanced analytics, and building scalable BI Solutions. At the Buehler Center, her work focuses on developing high-impact public health dashboards—including The OD Pulse, Comparing Community Profiles, Mass Shooting Dashboard—and on extracting, transforming, and integrating complex datasets to support research and data-driven decision-making. Shivangi holds a Master of Science in Information Technology from Northwestern University and brings a strong interdisciplinary background. Her previous work includes developing advanced machine learning models, data visualization and automated analytical workflows. She is particularly interested in bridging engineering, data science, and public health to develop robust, scalable solutions that translate complex data into actionable insights.

Spencer D. Cox, MBA

He/Him

Geospatial (GIS) Specialist 

Spencer Cox joined the Buehler Center at Northwestern University in February 2025 as a Geographic Information Systems (GIS) Specialist. He has worked in the fields of urban planning in Cincinnati, Ohio, and wildlife conservation for the State of California Department of Fish and Wildlife since graduating from his master’s program. Since joining Spencer has worked to integrate geographical data into the Buehler Center with his work centered on substance use and drug supply. Additionally, Spencer is involved with environmental health projects focusing on extreme heat and cirrhosis as well as extreme heat and substance use. He creates visualizations using ArcGIS including maps, dashboards, StoryMaps, and ArcGIS based web applications.

Yingxuan Liu, MA

She/Her

Research Data Analyst 

She is a computational social scientist with training in economics and advanced quantitative methods. Her work focuses on the analysis of large-scale surveillance datasets related to public health, including injury, violence, and substance use outcomes. She specializes in data engineering, time series analysis, statistical modeling, and has extensive experience working with complex, multi-source data. Her work also emphasizes data security and privacy-preserving workflows for sensitive data environments. Her methodological interests include synthetic data generation and the application of computational and machine learning approaches to scalable social and population health research. She has developed and maintained the Illinois SUDORS dashboard and collaborates closely with multidisciplinary research teams, providing technical leadership in secure data architecture, analysis, and visualization for private, federal and state-funded projects.