Meta-analysis on using CT for Screening COVID-19

Many hospitals in India have started using CT to screen all emergency patients or patients due for admission for COVID-19. Is this valid, given that organizations like ACR and STR have advised against CT screening? We review a meta-analysis published recently in Radiology comparing CT with RT-PCR to explain how CT screening doesn’t help in India as of now.

Essentially, CT has high sensitivity but low specificity. Thus, the positive predictive value (PPV) of CT depends on the prevalence of COVID-19 in that particular region. In countries with <10% prevalence (where we assume India to still fall), the positive predictive value of RT-PCR (range: 47.3%, 84.3%) is more than ten times higher than that of CT scans, which is single-digit (range: 1.5%, 8.3%). Clearly not good enough to be used for screening!

 

PS : If the embedded video is not opening, you can view the video on YouTube by clicking here.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s