Table 5. Multivariate regression of prognostic factors for pneumothorax complications.

Distances	Coef. (95% CI)	z	P value
Skin-chest wall distance	−0.071 (−0.141 to −0.000)	−1.99	0.048
Skin-tumor edge distance	0.208 (0.127 to 0.289)	5.09	<0.001
Skin-tumor center distance	0.168 (−0.018 to 0.355)	1.77	0.08
Chest wall-tumor center distance	−0.109 (−0.297 to 0.077)	−1.16	0.25
Tumor size	−0.075 (−0.148 to −0.003)	−2.07	0.04

Skin-chest wall distance: the distance from the skin to the chest wall, skin-tumor edge distance: the distance from the chest wall to the edge of the tumor, skin-tumor center distance: the distance from the chest wall to the tumor center, chest wall-tumor center distance: the distance from the chest wall to the tumor center. All the distances were measured at the section where the tumor is at largest size. Coef., coefficient; CI, confidence interval.