A recent study conducted by researchers from the Germans Trias i Pujol Research Institute (IGTP) has been published in the journal Scientific Reports, presenting a novel method to address selection biases in population-based cohorts. This advancement holds promise for enhancing the reliability of data obtained from such studies, thereby benefiting public health research and precision medicine.
The study focused on the GCAT cohort, which comprises nearly 20,000 adults from Catalonia and serves as a crucial platform for investigating the interplay between genetic and environmental factors in complex disease development. As the cohort ages, it offers valuable insights into disease incidence patterns. However, like many volunteer-based cohorts, GCAT is susceptible to healthy volunteer bias, wherein individuals in better health and with more favorable socioeconomic backgrounds are overrepresented compared to the general population. This disparity can undermine the generalizability of research findings to broader demographics.
Led by Natàlia Blay as the first author and under the guidance of Dr. Rafael de Cid, the scientific director of the GCAT project, the study also involved Dr. Conxa Violán from the Primary Care Research Support Unit of the Northern Metropolitan Area. This collaborative effort falls under the GRIMTra research group, integrated into IGTP’s CORE Program, which aims to bridge biomedical research, population data, and clinical practice.
To tackle the challenge of healthy volunteer bias, the researchers compared GCAT cohort data with health records and population surveys from Catalonia. By employing a statistical adjustment technique called raked weighting, which considers key variables such as age, sex, education level, smoking habits, and perceived health status, the team achieved a significant reduction in bias. This correction led to a 70% improvement in demographic variables and a 26% enhancement in disease prevalence estimations, making the cohort data more representative of the general population.
This approach not only ensures more precise and inclusive findings but also amplifies the potential of GCAT as a platform for implementing community-scale precision medicine initiatives and shaping evidence-based health policies. Dr. de Cid emphasized the value of the study, stating that it enhances the GCAT cohort’s role as a population laboratory for disease mechanism exploration and evidence generation for public health interventions.
The findings of this study have been published in Scientific Reports under the title “Weighting health-related estimates in the GCAT cohort and the general population of Catalonia.” This research contributes to advancing translational research in public health and underscores the importance of addressing cohort representativeness to derive meaningful insights for improving community health outcomes.
For more information, refer to the original article: DOI: 10.1038/s41598-025-01284-9. This research was conducted by the Germans Trias i Pujol Research Institute.
