Rates of serious clinical outcomes in survivors of hospitalisation with COVID-19: a descriptive cohort study within the OpenSAFELY platformThe OpenSAFELY Collaborative, Tazare J, Tazare J, Walker AJ, Tomlinson L, Hickman G, Rentsch CT, Williamson EJ, Bhaskaran K, Evans D, Wing K, Mathur R, Wong AY, Schultze A, Bacon S, Bates C, Morton CE, Curtis HJ, Nightingale E, McDonald HI, Mehrkar A, Inglesby P, Davy S, MacKenna B, Cockburn J, Hulme WJ, Hulme WJ, Warren-Gash C, Bhate K, Nitsch D, Powell E, Mulick A, Forbes H, Minassian C, Croker R, Parry J, Hester F, Harper S, Eggo RM, Evans SJ, Smeeth L, Douglas IJ, Goldacre B.