Abnormality

Grade assigned

Anatomical regions scored

Parenchymal opacification alone
Parenchymal opacification > reticular pattern extent
Parenchymal opacification = reticular pattern extent
Reticular pattern extent > parenchymal opacification
Reticular pattern alone

1
2
3
4
5

Lobes scored independently of each others

Maximum score = 5 per lobe

Variations of this method also used by Pignone et al. [2]; Davas et al. [10]; Shahin et al. [11]; Giacomelli et al. [12]; Shah et al. [13]; Gohari Moghadam [14].