COVID-19 pandemic(16) COVID-19(16) diagnostic(14) imaging(13) Patient(8) population level(6) Local(6) change(6) trauma patient(6) Society(6) predicted(6) Algorithm(6) patients(6) London(6) Accuracy(6) rates of infection(6) imaging diagnostic(6) Computed tomography(6) Chest(4) abdominal pain(4) evaluated(4) National(4) correlation(4) coronavirus disease(4) Elective surgery(4) sensitivity(4) with COVID-19(4) positive(4) Surveillance(4) lung(4)