Table 1

Variables and range used for computation of the paw score standardisation using quartile range

Points on paw score
Variables0123
PaO2 (mm Hg)≥64.5(51.5–64.4)(46.5–51.4)<46.5
%CSA<5 <0.313(0.313–0.432)(0.433–0.547)≥0.548
WT<1.095(1.095–1.179)(1.180–1.324)≥1.325
• WT, mean wall thickness; %CSA<5, percentage of total lung area taken up by the cross-sectional area of pulmonary vessels less than 5 mm2.