Statistically compare PCNSL trial demographics with population demographics to determine how well US trials reflect population demographics. Geographically analyze the distribution and level of urbanization of trials across the US.

Primary Central Nervous System Lymphoma (PCNSL) is a rare and aggressive malignant brain cancer affecting, on average, 1,500 people in the US annually. Currently, there is limited demographic data showing which patients have enrolled nationally in PCNSL clinical trials

Data was collected on median age, gender, ethnicity, and race in US PCNSL trials from ClinicalTrials.gov dating from 1995-present and compared to US population demographics obtained from the CBTRUS Statistical Report: Primary Brain and Other Central Nervous System Tumors Diagnosed in the United States in 2013–2017. Zip codes were gathered for trial locations and their level of urbanization was determined using the Rural-Urban Commuting Area Codes.

US PCNSL trials were located primarily in metropolitan areas. The trial median age was lower than the population median age and Black/African Americans and Hispanics were underrepresented in trials compared to the US population. Due to disparities between PCNSL trials and the population, data gathered from these trials may be biased towards treating a certain demographic and not accurately represent the entire US population demographic.