Determining the Risk of Developing Symptomatic SARS-COV2-19 Infection After Attending Hospital for Radiological Examinations: a Controlled Cohort Study

Since March 2020, the novel coronavirus (COVID-19) pandemic has caused considerable disruption to the provision of routine healthcare in the UK. A key priority for healthcare providers when gaining control of COVID-19, is to restart the provision of urgent non-COVID care. There are several barriers including a reluctance for people to attend hospital appointments for fears of contracting COVID-19. Although SARS-COV2 infections have been reported to occur during hospital inpatient stay, the risk of acquiring SARS-COV2 during outpatient consultations or radiological investigations has not been reported.

In a pilot study at our hospitals during the pandemic, we have found radiology to reliably record in person attendance contrary to outpatient clinic appointments records that were contaminated by remote consultations. The investigators will calculate the incidence of infection in approximately 30,000 patients at Nottingham and 17,000 patients at Cardiff and calculate the risk of infection within 28 days of attending outpatient radiology appointments. Controls will use data on patients who attended the hospitals in 2019.

The study team will utilize the data held in the electronic systems of NUH and University Hospital of Wales to perform a cohort study which will comprise both an exposed cohort and unexposed cohort.

The exposed cohort will comprise patients who attended outpatient radiology appointments during (between 29/1/20 - 24/5/20) and whether they subsequently developed a positive or negative PCR test for Sars-CoV2 result within 28-days of their attendance. The unexposed cohort will work as a control group, comprising individuals who attended outpatient radiology appointments during the equivalent period in 2019.

All of this data will be retrospective, so will not require any additional data collection, nor will it interfere with routine clinical care. Pseudo-anonymised data will be transferred from University Hospital of Wales in Cardiff to Nottingham University Hospitals (NUH) Trust via a password-protected, encrypted spreadsheet, with original patient identifiers removed, and a unique code assigned, that only the researcher in Cardiff can use to trace back to the individual, this is so all the analysis can be performed at NUH by a Nottingham based statistician.