Defining the Subtypes of Long COVID and Risk Factors for Prolonged Disease: Population-Based Case-Crossover Study

Skyler Resendez   ¹ , DPhil ;   Steven H Brown   ² , MD ;   Hugo Sebastian Ruiz Ayala   ¹ , MSc ;   Prahalad Rangan   ¹ , DPhil ;   Jonathan Nebeker   ² , MPH, MD ;   Diane Montella   ² , MD ;   Peter L Elkin   ^{1, 2} , MD

¹ Department of Biomedical Informatics, University at Buffalo, State University of New York, Buffalo, NY, United States

² Office of Health Informatics, Department of Veterans Affairs, Washington, DC, United States