Table 4

Survival of treated children categorised by age, sex, white blood cell count, immunophenotype and Down’s syndrome status

		5 year % survival (SE)		All children			First 3 months			3 months to 2 years			After 2 years
		5 year % survival (SE)		O	E	p Value		O	E	p Value		O	E	p Value		O	E	p Value
Age at diagnosis (years)
0	37 (3.8)	107	61.6	< 0.0001		24	11.6	< 0.0001		58	32.8	< 0.0001			17.4	< 0.0001
1–4	81 (0.8)	584	738.9			75	80.2			163	231.1			346	427.5
5–9	74 (1.2)	433	422.7			36	50.5			162	160.6			235	211.6
10–14	61 (1.7)	363	263.8			47	39.7			156	114.6			160	109.5
Sex
Male	73 (0.9)	919	837.6	< 0.0001		94	105.8	0.064		323	313.8	0.40		502	418.5	< 0.0001
Female	77 (0.9)	568	649.4			88	76.2			216	225.2			264	347.5
White blood cell count (× 10⁹/l)
0–49	80 (0.7)	928	1068.7	< 0.0001		102	116.0	< 0.0001		267	339.9	< 0.0001		559	611.3	< 0.0001
50+	57 (1.5)	518	377.7			72	59.4			260	183.5			186	134.3
NR	70 (4.2)	41	41.6			8	6.6			12	15.6			21	20.4
Immunophenotype
Common (incl. pre-B)	81 (0.7)	847	971.6	< 0.0001		80	109.0	< 0.0001		213	315.1	< 0.0001			547.4	0.44
T cell	51 (2.1)	286	214.7			42	27.2			173	106.9			71	80.7
B cell	51 (5.9)	38	18.8			13	3.3			20	6.6			5	8.8
Null	56 (3.2)	120	107.4			17	19.2			63	51.6			40	36.7
NR	71 (1.9)	196	174.5			30	23.3			70	58.8			96	92.4
Down’s syndrome
Yes	57 (5.7)	39	15.6	< 0.0001		9	2.2	< 0.0001		15	4.8	< 0.0001		15	8.6	0.041
No	75 (0.6)	1448	1471.4			173	179.8			524	534.2			751	757.4

The expected numbers of deaths and log rank tests for each variable were based on a stratified analysis allowing for all four other variables.
O, observed deaths; E, expected deaths; P, two sided p value from log rank test; NR, not recorded.