Hi Team, For some reason the last rows of the Respiratory Viral Results table are full of Null values except participant_id. So when we filter on non-null rows we only get 202 Flu patients and 752 flu-negative patients, we were expecting 202 Flu and 774 flu-negative patients based on : https://journals.asm.org/doi/10.1128/jcm.02070-21 Do you have any explanation ? Thank you very much for your help. Best regards, Oscar Mallet