Walker AJ, MacKenna B, Inglesby P, Tomlinson L, Rentsch CT, Curtis HJ, Morton CE, Morley J, Mehrkar A, Bacon S, Hickman G, Bates C, Croker R, Evans D, Ward T, Cockburn J, Davy S, Bhaskaran K, Schultze A, Williamson EJ, Hulme WJ, McDonald HI, Mathur R, Eggo RM, Wing K, Wong AY, Forbes H, Tazare J, Parry J, Hester F, Harper S, O’Hanlon S, Eavis A, Jarvis R, Avramov D, Griffiths P, Fowles A, Parkes N, Douglas IJ, Evans SJ, Smeeth L, Goldacre B, . Clinical coding of long COVID in English primary care: a federated analysis of 58 million patient records in situ using OpenSAFELY. British Journal Of General Practice 2021, 71: bjgp.2021.0301. PMID: 34340970, PMCID: PMC8340730, DOI: 10.3399/bjgp.2021.0301.Peer-Reviewed Original Research