Table IV.

Comparison of non-parametric data for groups 1-2-3 (percent values given) (Kruskal-Wallis test was used)

Parameter		Group 1 (age 4–12) (n = 33)	Group 2 (age 13–19) (n = 474)	Group 3 (age > 20) (n = 525)	P-value
Gender:					0.226
	Male	30 (91%)	403 (86%)	486 (93%)
	Female	3 (9%)	69 (14%)	39 (7%)
Diagnosis, %:					0.102
	Pectus excavatum	99.1	92	97
	Pectus carinatum	0.9	5	3
	Mixed type	0	3	0
Symptom, %:					0.331
	Yes	6	14	16
	No	94	86	84
Echocardiographic finding, %:					0.371
	Yes	9	18	23
	No	91	82	77
Electrocardiographic finding, %:					0.309
	Yes	0	6	9
	No	100	94	91
Post-surgical pneumothorax, %:					0.840
	Yes	0	1	1
	No	100	99	99
Complication, %:					0.928
	Yes	0	1	1
	No	100	99	99
Number of bars, %:					0.028
	One	100	55	45
	Two	0	45	55
Pre-surgical vacuum, %:					0.970
	Yes	0	0	0
	No	100	100	100
Steel wires, %:					0.002
	Yes	9	88	73
	No	91	12	27
Stabilizer, %:					< 0.001
	Yes	45	98	94
	No	55	2	6
Bilateral incision:					0.046
	Yes	9	37	46
	No	91	63	54
Callus tissue, %:					0.034
	Yes	0	9	26
	No	100	91	74
Bleeding, %:					0.583
	Yes	0	1	0
	No	100	99	100