Table 5. Doubling times in volume and mass of the different nodule types.

Nodule types	VDT (mean ± SD) (days)	MDT (mean ± SD) (days)	P value
Pure GGNs	848±330	655±225	0.002
Part-solid nodules	598±229	462±183	0.001
Solid nodules	267±91	230±73	<0.001
P value	<0.001*#$	<0.001*#$	–

The data formats of VDT and MDT are mean ± SD. *, P<0.05, doubling times of pure GGNs versus part-solid nodules; ^#, P<0.05, doubling times of pure GGNs versus solid nodules; ^$, P<0.05, doubling times of part-solid nodules versus solid nodules. VDT, volume doubling time; MDT, mass doubling time; SD, standard deviation; GGN, ground-glass nodule.