Table 3.

Factors Associated with the Rate of Respiratory Infectious Episodes (RIE)

Factors Associated with Rate of Respiratory Infectious Episodes		Sample N (%) or Mean (SD) at 1 year of age	Association with RIE rate
			RIE Rate Ratio+	95% CI		p-value
Socio-demographic Measures
Study Site	Colorado	909 (16.2)	1.00	reference
	Georgia/Florida	526 (9.4)	1.14	1.08	1.20	<0.001
	Washington	741 (13.2)	1.04	0.99	1.09	0.12
	Finland	1225 (21.8)	1.43	1.37	1.50	<0.001
	Germany	305 (5.4)	1.21	1.13	1.30	<0.001
	Sweden	1912 (34.0)	1.27	1.22	1.32	<0.001
Child Age	Years	1	0.86	0.85	0.87	<0.001
Child Gender	Boy	2844 (50.6)	1.00	reference
	Girl	2774 (49.4)	0.95	0.93	0.97	<0.001
Child Ethnic Minority	No	4727 (86.3)	1.00	reference
	Yes	750 (13.7)	0.89	0.86	0.93	<0.001
Only Child	No	3187 (57.2)	1.00	reference
	Yes	2388 (42.8)	0.96	0.94	0.98	<0.001
Parents married or living together	No	210 (3.8)	1.00	reference
	Yes	5367 (96.2)	1.07	1.01	1.13	0.03
Maternal Education	Primary school	1035 (18.5)	1.00	reference
	Secondary/trade school	1303 (23.3)	1.05	1.01	1.10	0.01
	College	3249 (58.2)	1.14	1.10	1.18	<0.001
Started Day Care	No	1150 (20.5)	1.00	reference
	Yes	4468 (79.5)	1.26	1.23	1.31	<0.001
Season	Spring/Summer	2852 (50.8)	1.00	reference
	Fall/Winter	2766 (49.2)	1.30	1.28	1.31	<0.001
Maternal Lifestyle Behaviors
Smoked	No	5108 (91.5)	1.00	reference
	Yes	476 (8.5)	0.91	0.87	0.95	<0.001
Worked Outside Home	No	3596 (64.7)	1.00	reference
	Yes	1963 (35.3)	0.97	0.95	1.00	0.02
Maternal Perception of Child’s T1D Risk
Accurate	No	2102 (37.5)	1.00	reference
	Yes	3500 (62.5)	1.06	1.04	1.09	<0.001

First degree relative (FDR) status, mothers age at child’s birth, maternal anxiety about child’s T1D risk, and household size were not associated with rate of mother reported child RIEs (p values >0.10). Note:

⁺Rate Ratio (RR) = RIE rate relative to RIE rate in reference group; RR >1 indicates higher rate relative to reference group, RR <1 lower rate.