In most CT scan reports of patients suspected to have Covid-19 pneumonia, there will be a mention of a CO-RADS score. This is used to communicate the extent of likelihood of the scan showing findings suggestive of Covid-19 or not.
CO-RADS 1 – Unlikely, CO-RADS 2 – Low, CO-RADS 3 – Indeterminate, CO-RADS 4 – Level of suspicion high, CO-RADS 5 – Classic findings
Prokop M et al. Radiology 2020;Apr 27:online first.
The image shows the various patterns of CO-RADS. When we say CO-RADS 1 or 2, then the chance of Covid-19 is very low. When we say CO-RADS 4 or 5, the chance that the patient has Covid-19 is very high.