Table 1.

Clinical and biologic characteristics of the training and validation cohorts

	Training	Validation
Characteristics	Training set (N = 96)	Set 1 (N = 120)	Set 2 (N = 101)	Set 3 (N = 251)
Age, mo
Median	18.94	26.9	16.3	15.03
Range	0–216	0–299	0–156	0–276
INSS, n (%)
Stage I–III	53 (56)	43 (36)	51 (50)	153 (61)
Stage IV	34 (35)	52 (43)	50 (50)	67 (27)
Stage IVS	9 (9)	25 (21)	—	31 (12)
MYCN status, n (%)
Amplified	20 (21)	24 (20)	20 (20)	30 (12)
Nonamplified	76 (79)	96 (80)	81 (80)	220 (88)
Undetermined	—	—	—	1
1p status, n (%)
LOH	11 (25)	31 (26)	28 (28)	52 (21)
No LOH	33 (75)	88 (73)	72 (72)	194 (79)
Undetermined	52	1	1	5
Follow-up, mo
Median	48.22	89.21	11.73	64.46