Table 2.

Inclusion of perinatal data and parental diabetes. The variables in the table may be responsible for some of the effects on type 1 diabetes risk falsely ascribed to the presence of autoantibodies, i.e. may be confounders.

Variables	Hazard ratio (HR)	95% CI	P<
Tenfold increase in RU  autoantibodies	2.23	1.66–3.01	0.0001
Birth length – per cm	0.91	0.97–1.04	0.91
Birth weight – per kg	1.03	0.87–1.23	0.71
Gestational age – per week	1.00	0.95–1.04	0.84
Maternal age – per 10 years	1.22	1.02–1.489	0.03
Paternal age – per 10 years	0.93	0.80–1.09	0.37
Sex, male versus female	1.05	0.93–1.20	0.42
Maternal type 1 diabetes	4.23	2.29–7.81	0.0001
Paternal type 1 diabetes	7.31	4.71–11.35	0.0001

By inclusion into the statistical model, the individual increases/decreases in type 1 diabetes risk belonging to each variable are listed including the level of significance (P value) and confidence interval (CI).