Table 3. Results of logistic regression analysis.

Items	B	S.E.	wald	df	P	OR	95% C.I for Exp (B)
Items	B	S.E.	wald	df	P	OR	lower	upper
Tumor locations			4.567	2	0.102
Upper lobe	0^a
Middle lobe	0.895	0.759	1.393	1	0.238	2.448	0.553	10.829
Lower lobe	–0.588	0.373	2.482	1	0.115	0.555	0.267	1.154
Maximum tumor diameter			10.834	3	0.013
≤3 cm	0^a
>3 cm but ≤5 cm	0.75	0.508	2.179	1	0.140	2.117	0.782	5.729
>5 cm but ≤7 cm	1.559	0.573	7.398	1	0.007	4.754	1.546	14.622
>7 cm	1.648	0.600	7.558	1	0.006	5.198	1.605	16.832

^aThis parameter is set to zero because it is redundant