Table 4.

Association of two histologically defined categories of SIDS with covariates compared to healthy, age-matched Dutch controls (n = 2,841). P-values and odds ratios for the two largest SIDS categories defined by histological findings; genuine SIDS, no findings that might have had any influences on survival; SIDS with minor infections, e.g. laryngitis, urine bladder infection, etc. P-values calculated with two-tailed Fishers’ exact test, OR and 95% CI for OR of the binary logistic regression of all covariates. Prone sleeping 1 is primary prone sleeping; prone sleeping 2 is secondary prone sleeping; supine sleeping is indicator. Postnatal smoking 1 is one parent smokes; postnatal smoking 2 is both parents smoke; no postnatal parental smoking is indicator. Education parents 1 is both low; education parents 2 is one low; both high educated is indicator. Ethnical origin parents 1 is one European Caucasian, one non- European Caucasian; ethnical origin parents 2 is both non-European Caucasian; both European Caucasian is indicator

Covariate	1				2
	Significance	Odds ratio	95.0% C.I. for OR		Significance	Odds ratio	95.0% C.I. for OR
			Lower	Upper			Lower	Upper
Genuine SIDS (n = 100)
Prone sleeping	<0.001	17.1	6.99	41.9	<0.001	102.1	41.4	251.7
Postnatal smoking	0.143	1.91	0.80	4.53	0.007	5.02	1.56	16.16
Premature birth	0.21	1.75	0.73	4.18
Gender	0.39	1.36	0.68	2.71
Education parents	0.28	1.71	0.65	4.47	0.73	1.21	0.42	3.44
Ethnical origin parents	0.18	1.85	0.75	4.53	0.35	0.32	0.03	3.38
Lack of breastfeeding	0.13	0.56	0.26	1.18
Maternal prenatal smoking	0.67	1.75	0.45	3.46
SIDS with minor infection (n = 28)
Prone sleeping	<0.001	49.9	13.2	188.5	<0.001	153.6	32.8	720.4
Postnatal smoking	0.14	2.86	0.70	11.6	0.045	6.76	1.04	43.9
Premature birth	0.045	3.66	1.03	12.9
Gender	0.19	0.43	0.12	1.51
Education parents	0.90	1.10	0.23	5.22	0.78	0.78	0.13	4.55
Ethnical origin parents	1.00	0.00			1.00	0.00
Lack of breastfeeding	0.53	0.67	0.19	2.37
Maternal prenatal smoking	0.52	1.61	0.37	7.02