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Methods: Mind the Gap

Webinar Series

Design and Analysis of Individually Randomized Group-Treatment Trials in Public Health

April 24, 2018
Sherri Pals, Ph.D.
Sherri Pals, Ph.D.

Mathematical Statistician
Centers for Disease Control and Prevention 

View the Webinar

About the Webinar

Individually randomized group-treatment (IRGT) trials are studies in which individual participants are randomly assigned to study conditions, but treatment is administered in groups. Because participants share a group environment and interact with each other, observations taken on participants may be correlated within treatment groups.

This correlation must be taken into account in design and analysis of IRGT trials, and many appropriate methods may be drawn from the literature on group-randomized (or cluster-randomized) trials (GRTs). However, there are important differences between GRTs and IRGT trials, and more work is needed to adapt GRT methods or develop new methods.

This webinar provides an introduction to IRGT trials, reviews current approaches to design and analysis, and highlights areas where further work is needed.

About Sherri Pals

Sherri Pals obtained her Ph.D. in experimental psychology with a concentration in research design and statistics in 2002, and a master’s degree in mathematical statistics in 2003, both from the University of Memphis. She joined the Division of HIV/AIDS Prevention at the Centers for Disease Control and Prevention in 2002 as a mathematical statistician, and remained with that division for eight years. After discovering a love for international work, Dr. Pals moved to the Division of Global HIV and Tuberculosis in 2010.

In her work in domestic and international HIV/AIDS and tuberculosis, she has designed and analyzed numerous GRTs, and enjoys teaching and mentoring others in this area. She has also authored and co-authored several manuscripts on design and analysis of clustered studies, including GRTs and IRGT trials.