Common protocol for validation of the QCOVID algorithm across the four UK nations (BMJ Open, 2022)

(untitled) - Kerr, S; Robertson, C; Nafilyan, V; Lyons, RA; Kee, F; Cardwell, CR; Coupland, C; Lyons, J; Humberstone, B; Hippisley-Cox, J; Sheikh, A