Table 1.

Characteristics of the Study Patients with Leukaemia, Intracranial Malignancy and Lymphoma from the CICD and of the Comparison Controls from the LHID 2010.

Variables	Leukaemia		Control		p value	Intracranial malignancy		Control		p value	Lymphoma		Control		p value
	(n = 1423)		(n = 14230)			(n = 838)		(n = 8380)			(n = 272)		(n = 2720)
	n	%	n	%		n	%	n	%		n	%	n	%
Gender					1.000					1.000					1.000
Male	791	55.6	7910	55.6		479	57.2	4790	57.3		169	62.1	1690	62.1
Female	632	44.4	6320	44.4		359	42.8	3590	42.7		103	37.9	1030	37.9
Age on index day*					1.000					1.000					1.000
≤6	1103	77.5	11030	77.5		542	64.7	5420	64.7		115	42.3	1150	42.3
>6	320	22.5	3200	22.5		296	35.3	2960	35.3		157	57.7	1570	57.7
Urbanization level					1.000					1.000					1.000
1 (city)	400	28.1	4000	28.1		217	25.9	2170	25.9		76	27.9	760	27.9
2	701	49.3	7010	49.3		378	45.1	3780	45.1		120	44.1	1200	44.1
3	207	14.6	2070	14.6		147	17.5	1470	17.5		40	14.7	400	14.7
4 (villages)	115	8.1	1150	8.1		96	11.5	960	11.5		36	13.2	360	13.2
CT: one-year exclusion period					0.853					<0.001					0.247
Yes	34	2.4	329	2.3		45	5.4	240	2.9		13	4.8	93	3.4
No	1389	97.6	13901	97.7		793	94.6	8140	97.1		259	95.2	2627	96.6
CT: two-year exclusion period					0.494					0.031					0.860
Yes	21	1.5	245	1.7		29	3.5	190	2.3		7	2.6	75	2.8
No	1402	98.5	13985	98.3		809	96.5	8190	97.7		265	97.4	2645	97.2

Abbreviations: LHID = Longitudinal Health Insurance Database; CICD = Catastrophic Illness Certificate Database; CT = computed tomography.

*The index date was the disease diagnosis date in the disease group and the corresponding date in the non-diseased group.