Table 2.

characteristics of the study participants by diabetes status.*

	Controls (n = 67)		Type 1 diabetes cases (n = 128)
Variable	Median	Min, Max	Median	Min, Max	P
Age at diagnosis, y	--	--	3.0	0.16, 6.0	--
Age at recruitment, y	5.0	0.4,10.0	6.0	2.0, 10.0	0.05
Birth weight, kg	3.32	2.3, 4.7	3.32	1.11, 4.91	0.94
Total iron: form., suppl. & breast milk, mg	466	50, 1224	1159	50, 2399	< 0.0001
Iron from formula & supplements, mg	466	0, 1213	1144	0, 2399	< 0.0001
Duration of feeding low-iron formula, wks	12	0, 16	0	0, 16	< 0.0001
Duration of feeding high-iron formula, wks	12	0, 32	10	0, 16	0.10
Duration of breast feeding, wks	12	0, 16	4	0, 16	0.001
Mother had gestational diabetes, %	0		3		0.30
Mother has diabetes, %	3		4		1.00
Sibling rank, %
First	42		49		0.44
Second	49		42
Third	6		8
Forth or higher	3		1

* Values are medians, minimum, maximum or percentages.

†P values are from the Wilcoxon rank sum test for continuous variables and from the Fisher's exact test for categorical variables.