March 2026

CASSIDY and the Computable Phenotype

Dr. Annemarie Hirsch, an epidemiologist in Geisinger’s Department of Population Health Sciences, and the director of the Center for Community Environment and Health, is leading a new study focused on understanding the prevalence and burden of diabetes in children and your adults. CASSIDY, short for Comprehensive Analysis, Surveillance, and Statistics Initiative for Diabetes in the Young, seeks to estimate the prevalence and incidence of diabetes by type, using EHR data from two large health systems in Pennsylvania, Geisinger and UPMC. Together, these health systems serve patients in all but four of 67 counties in Pennsylvania. CASSIDY builds on the work done by Hirsch and her team in their previous study: Assessing the Burden of Diabetes by Type in Children, Adolescents, and Young Adults (DiCAYA).

Both CASSIDY and DiCAYA focused on the creation of computable phenotypes to define their population of interest. If, like most people, you have never heard of a computable phenotype, think of it as a reusable set of rules for identifying patients using the Electronic Health Record (EHR). Computable Phenotypes are used to quicky identify patient groups using structured data found in the EHR, including demographics, diagnoses, lab results, and sometimes even provider notes. They enable efficient cohort identification, clinical trial recruitment, quality measurement, and safety surveillance, and can often replace manual chart reviews.

Hirsch and her team, which includes Dr. Jonathan Arnold at the University of Pittsburgh, will also be looking at the prevalence of risk factors for diabetes complications as well as the use of diabetes medications among children and young adults with diabetes. Early onset of diabetes is associated with increased risk of complications, and the study team hopes that improved disease surveillance will result in increased resources for children and young adults with diabetes, not just in Pennsylvania, but across the country.

For more information about computable phenotypes, see Robert Tasker’s article “Why everyone should care about Computable Phenotypes”.

«—- Back To News