no intervention

proportion of patients presented with fever, proportion of patients refered to fever clinics, proportion of patients screened for COVID-19, method of screening (CT? nucleated acid test?)

proportion of patients on whom fever occured, proportion of patients screened for COVID-19, method of screening (CT? nucleated acid test?)

Duration of operation (≥180min/<180min); Intra-operative transfusion (Y/N); Surgical approach (Laparoscopy-involved/Open); Resection range (Non-radical/Radical); Lymph node dissection (Unknown/Not dissected/D1/D2 or above); Combined organ resection (Y/N); Post-operative complications (Y/N); Post-operative transfusion (Y/N); Post-operative hospital stay (≥7d/<7d)

Out-patient of surgery (Open/Closed); Emergency of surgery (Open/Closed); Fever clinic (Open/Closed); Surgical ward (Open/Closed); Functional level of surgical ward (Receive emergency surgery patients only/Receive surgery patients only/Receive all kinds of patients); Isolation ward for suspected COVID-19 patients (With/Without); Bed number in each surgical ward room (1/2/≥3); Isolation area within surgical ward (With/Without); Usage of sub-pressure operation theaters (Routinely applied/Applied for suspected patients/Never applied); Protection level of surgeons in surgical ward (No specific protection/Regular medical masks/Any of N95 mask, eye/face shields, gowns); Protection level of surgeons in ER room (No specific protection/Regular medical masks/Any of N95 mask, eye shields, face shields, gowns)