TL;Dr.: In a study published in JAMA, Geng and colleagues updated the research index classification for adults with long COVID (LC) or post-COVID-19 condition using additional data from 13,647 adults participating in the RECOVER-Adult study (median age, 45; 73% female) and an expanded symptom list built using input from patient communities. Some symptoms included in the 2024 index were postexertional malaise, fatigue, brain fog, dizziness, palpitations, change in smell or taste, thirst, chronic cough, chest pain, shortness of breath, and sleep apnea. With the updates, a score of 11 or greater was considered the optimal threshold for identifying participants with highly symptomatic LC. Using the new index, 20% of participants with known prior SARS-CoV-2 infection and 4% without known prior infection were considered as having likely LC, and 39% of those with known prior SARS-CoV-2 infection were classified as having possible LC, a new category. These updates emphasize the need for continued refinement to improve classification of LC and its subtypes as understanding evolves.