Table 1.

Association of SIDS (n = 142) with covariates compared to healthy, age-matched Dutch controls (n = 2,841). P-values and odds ratios for the entire case group. P-values calculated with two-tailed Fishers’ exact test, OR and 95% CI for OR of the binary logistic regression of all covariates. Multivariate analysis 1 is with postnatal smoking considered none; one or both parents smoking postnatal as one covariate. Multivariate analysis 2 is with postnatal smoking considered maternal or paternal postnatal smoking as two separate covariates

Covariate	Cases		Controls		Univariate analysis	Multivariate analysis 1				Multivariate analysis 2
								95% CI interval				95% CI interval
	N	%	N	%	P-value	P-value	OR	Lower	Upper	P-value	OR	Lower	Upper
Gender
Female	61	43	1,403	49
Male	81	57	1,434	51	0.44	0.97	0.99	0.56	1.76	0.86	0.95	0.53	1.69
Premature
No	76	74	2,492	89
Yes	27	26	317	11	<0.001	0.013	2.41	1.20	4.81	0.011	2.45	1.23	4.89
Parental education
Both high	17	24	797	30
One high	13	18	827	31	0.031	0.87	1.06	0.51	2.21	0.88	1.06	0.51	2.20
Both low	41	58	1,022	39	0.003	0.32	0.65	0.28	1.51	0.32	0.65	0.28	1.51
Parental ethnicity
Both European	73	81	2,130	83
One European	8	9	341	13	0.81	0.96	0.98	0.41	2.35	0.98	0.99	0.41	2.37
Both non-European	9	10	99	4	0.81	0.35	0.42	0.07	2.53	0.36	0.44	0.07	2.60
Started breastfeeding
Yes	50	60	2,264	80
No	33	40	559	20	0.002	0.19	0.65	0.35	1.24	0.25	0.68	0.36	1.31
Prone sleeping
No	52	46	2,715	96
Primary	36	32	83	3	<0.001	<0.001	21.48	10.62	43.46	<0.001	19.97	9.75	40.93
Secondary	24	21	27	1	<0.001	<0.001	100.5	45.96	219.6	<0.001	100.6	46.26	218.8
Prenatal maternal smoking
No	50	65	2,438	87
Yes	27	35	376	13	<0.001	0.48	1.36	0.58	3.16	0.72	1.20	0.46	3.15
Postnatal parental smoking
None	28	33	1,895	67
One	30	36	653	23	0.008	0.011	2.49	1.24	5.03
Both	26	31	260	9	<0.001	0.001	5.77	2.15	15.53
Postnatal maternal smoking
No	47	57	2,431	86
Yes	36	43	396	14	<0.001					0.04	2.67	1.04	6.35
Postnatal paternal smoking
No	35	44	2,026	72
Yes	45	56	792	28	<0.001					0.006	2.41	1.28	4.53