Table 5

Interaction between prenatal smoking and perinatal and postnatal characteristics of SIDS cases and controls in Scandinavia 1992 to 1995, the Nordic epidemiological SIDS study

CasesControlsOR95% CIpTest for interaction (p)
No%No%AdditiveMultiplicative
Prenatal smokingPoor sucking
NoNo8694.554590.71.0Reference0.070.010
NoYes55.5569.30.60.2 to 1.60.30
YesNo12786.423895.23.52.5 to 5.0<0.001
YesYes2013.6124.811.04.9 to 24.3<0.001
Prenatal smokingBreast feeding
NoYes6268.142570.11.0Reference0.310.80
NoNo2931.918129.91.20.7 to 2.00.45
YesYes6845.312750.83.82.5 to 5.8<0.001
YesNo8254.712349.25.13.3 to 7.9<0.001
Prenatal smokingInfection
NoNo2425.831251.21.0Reference0.170.15
NoYes6974.229748.82.91.7 to 4.7<0.001
YesNo4932.712248.25.43.1 to 9.3<0.001
YesYes10167.313151.89.55.7 to 15.8<0.001
Prenatal smokingAntibiotics
NoNo7075.350082.91.0Reference0.520.13
NoYes2324.710317.11.81.0 to 3.10.045
YesNo11275.719175.84.43.1 to 6.5<0.001
YesYes3624.36124.24.42.7 to 7.4<0.001
Prenatal smokingHospital admission
NoNo6266.748581.01.0Reference0.720.097
NoYes3133.311419.02.91.4 to 6.10.004
YesNo10771.818875.84.23.0 to 6.0<0.001
YesYes4228.26024.25.42.8 to 10.4<0.001
  • CI = confidence interval; OR = odds ratio.