Table 3. Chi-square tests of ordinal and nominal parameters in relation to SIR classification (n = 311).

Parameter	SIR0 (n = 144)	SIR1 (n = 134)	SIR2 (n = 8)	SIR3 (n = 7)	SIR4 (n = 18)	p value
Sex						0.72
Male	85(46%)	76(41%)	5(3%)	5(3%)	13(7%)
Female	59(47%)	58(46%)	3(2%)	2(1%)	5(4%)
Emphysema						0.001
Yes	32(49%)	18(28%)	2(3%)	3(5%)	10(15%)
No	112(46%)	116(47%)	6(2%)	4(2%)	8(3%)
Lesion lobar location						0.21
Rt upper	25(42%)	24(40%)	1(2%)	1(2%)	8(14%)
Rt lower	40(46%)	40(46%)	3(3%)	2(2%)	3(3%)
Rt middle	8(33%)	15(63%)	1(4%)	0(0%)	0(0%)
Lt upper	35(44%)	34(43%)	3(4%)	2(3%)	5(6%)
Lt lower	36(59%)	21(35%)	0(0%)	2(3%)	2(3%)
Lesion morphologic characteristic						0.05
Solid	106(43%)	110(45%)	5(2%)	6(3%)	17(7%)
Subsolid	32(67%)	13(27%)	2(4%)	0(0%)	1(2%)
Consolidative	4(40%)	6(60%)	0(0%)	0(0%)	0(0%)
Cavitary	2(22%)	5(56%)	1(11%)	1(11%)	0(0%)
Lesion histopathology						0.47
Malignant	93(45%)	93(45%)	7(3%)	4(2%)	10(5%)
Benign	32(50%)	28(44%)	0(0%)	2(3%)	2(3%)
Infection	10(50%)	7(35%)	0(0%)	0(0%)	3(15%)
Non-diagnostic	5(33%)	6(40%)	1(7%)	1(7%)	2(13%)
Patient position						0.90
Supine	58(45%)	59(46%)	4(3%)	2(2%)	6(5%)
Prone	75(48%)	62(39%)	4(3%)	4(3%)	11(7%)
Lateral	11(42%)	13(50%)	0(0%)	1(4%)	1(4%)
Number of pleural passes						<0.001
Once	66(64%)	28(27%)	2(2%)	1(1%)	6(6%)
Twice	61(48%)	58(46%)	2(2%)	0(0%)	5(4%)
3 times	16(26%)	34(57%)	3(5%)	4(7%)	3(5%)
4–5 times	1(5%)	14(63%)	1(5%)	2(9%)	4(18%)
Fissure puncture						<0.001
Yes	1(7%)	7(43%)	1(7%)	3(21.5%)	2(21.5%)
No	143(48%)	127(43%)	7(2%)	4(1%)	16(6%)
Needle-to-blood vessel angle						<0.001
No angle	144(48%)	127(42%)	7(3%)	4(1%)	17(6%)
Angle ≤90°	0(0%)	7(58.4%)	1(8.3%)	3(25%)	1(8.3%)

Frequency (% of respective row).