Supplementary Table 1 Non-SIDS and SIDS infant dataset

Characteristics / Non-SIDS (n=19) / SIDS (n=27) / F-value / P-value
Male: Female / 11:8 / 15:12 / F18,25 = 1.00 / 0.49
Post Conception Age at Death (months) / 14.5 ± 3.2 / 13.9 ± 2.9 / F1,38 = 0.58 / 0.59
Weight (kg) / 7.0 ± 2.5 / 6.8 ± 1.9 / F1,36 = 0.07 / 0.80
Length (cm) / 63.8 ± 8.3 / 62.2 ± 8.9 / F1,36 = 0.28 / 0.60
Brain weight (kg) / 0.8 ± 0.2 / 0.8 ± 0.2 / F1,34 = 0.34 / 0.56
Head circumference (cm) / 42.4 ± 4.8 / 41.5 ± 3.5 / F1,34 = 0.40 / 0.53
Risk factors
Prone sleep position / 31% / 55% / F18,25 = 0.92 / 0.05
Smoke exposure / 29% / 56% / F13,25 = 0.89 / 0.05
URTI / 38% / 46% / F12,24 = 0.98 / 0.44
Preterm / 38% / 16% / F7,22 = 1.78 / 0.26
Overweight BMI (>25) / 0% / 7% / F1,36 = 0.58 / 0.45
Autopsy/tissue related factors
Pulmonary oedema/aspiration/ congestion / 23%, 0%, 46% / 40%, 15%, 62% / F12,24 = 1.42 / 0.05. 0.03, 0.04
Petechiae: thymic/ lungs/epicardial / 0%, 0%, 5% / 59%, 41%, 41% / F12,24 = 0.37 / 0.03, 0.03, 0.05
Post mortem interval (hrs) / 35.4 ± 25.7 / 27.6 ± 17.7 / F1,38 = 1.25 / 0.27
Fixation duration (weeks) / 7.0 ± 2.8 / 6.3 ± 3.5 / F1,38 = 0.55 / 0.41

Non-SIDS causes of death: Septicaemia (n=3), Gastroenteritis (n=2), Bronchopneumonia (n=3), Myocarditis (n=3), Asphyxia due to direct suffocation (n=3), Cardiac failure from congenital heart disease (n=2), sudden accidental death/Undetermined (n=3). Undetermined is the term used where no specific diagnosis has been or can be made [86]. For these cases the diagnosis was given due to potential for drowning and for potential asphyxia.