Objective. The outbreak of coronavirus SARS-COV2 disease 2019 (COVID-19) necessitates fast and accurate diagnostic tools. RT-PCR has been identified as gold standard test with Chest-CT and Chest-Radiography showing promising results as well. However, several institutions are discouraging the use of radiological procedures for COVID-19 diagnosis, partly due to radiation risk. This study aimed to provide quantitative data towards an effective risk-to-benefit analysis for the justification of radiological studies in COVID-19 diagnosis to guide policy and decision makers.
Methods. The analysis was performed in terms of mortality rate per age group. COVID-19 mortality was extracted from epidemiological data across 159,107 patients in Italy. For radiological risk, the study considered 659 Chest-CT performed in adult patients. Organ doses were estimated using a Monte Carlo method and then used to calculate the Risk Index that was converted into a related 5-year mortality rate (SEER, NCI).
Results. COVID-19 mortality showed a rapid rise for ages >30 years old (min:0.30%; max:30.20%), whereas only 1 death was reported in the analyzed patient cohort for ages <20 years old. The rates decreased for radiation risk across age groups. The median mortality rate across all ages for Chest-CT and Chest-Radiography were 0.72% (min:0.46%; max:1.10%) and 0.03% (min:0.02%; max:0.04%), respectively.
Conclusions. COVID-19, Chest-Radiography, and Chest-CT mortality rates showed different magnitudes and trends across age groups. In higher ages, COVID-19 risk far outweighs that of radiological exams. Based on risk comparison alone, Chest-Radiography and Chest-CT for COVID-19 care is justified for patients older than 30 and 50 years old, respectively.