SIDS | Controls | Univariate* | Multivariate† | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
n | (%) | n | (%) | OR (95% CI) | p value‡ | p value§ | OR (95% CI) | p value‡ | p value§ | ||
*Adjusted for infant age in a conditional logistic regression model. | |||||||||||
†Adjusted for infant age, birth centile, higher parity, parental unemployment, moving house more than once in the last year, young maternal age, maternal smoking during pregnancy, postnatal exposure to tobacco smoke, any episode of lifelessness, and for the last sleep: sleeping position put down (side or prone), bed sharing, sofa sharing, sleeping outside the parental bedroom, and if not being tested for an interaction; also the following: recent infant illness, recent maternal alcohol consumption, lack of recent sleep, change in usual routine, using a dummy, bedding and clothes higher than 10 tog, and found with head covered by bedding. | |||||||||||
‡p value relates to the significance of the combined effects odds ratio. | |||||||||||
§p value relates to the interactions between the different factors and being small at birth, e.g. change in routine × being small at birth. | |||||||||||
¶Change in usual parental routine and infant care in the 24 hours prior to the last sleep (including going on holiday, visiting distant friends, or receiving visitors). | |||||||||||
**Defined as those who scored more than 7 (i.e. moderate illness or worse) using a revised version of the Cambridge Baby Check score. | |||||||||||
††Clothing and bedding (excluding bedding under the infant or nappy) with a total thermal resistance greater than 10 tog. | |||||||||||
Change in routine last 24 hours¶ | Small at birth | ||||||||||
No | No | 190 | (59.6) | 1028 | (80.0) | 1.00 (ref group) | 1.00 (ref group) | ||||
Yes | No | 46 | (14.4) | 156 | (12.1) | 1.95 (1.28 to 2.99) | 0.002 | 2.30 (1.02 to 5.19) | 0.046 | ||
No | Yes | 63 | (19.7) | 92 | (7.2) | 3.62 (2.46 to 5.32) | <0.0001 | 5.25 (2.42 to 11.39) | <0.0001 | ||
Yes | Yes | 20 | (6.3) | 9 | (0.7) | 10.60 (4.15 to 27.08) | <0.0001 | 0.44 | 11.79 (2.03 to 68.54) | 0.006 | 0.65 |
Illness in last 24 hours** | Small at birth | ||||||||||
No | No | 184 | (58.2) | 1097 | (85.4) | 1.00 (ref group) | 1.00 (ref group) | ||||
Yes | No | 50 | (15.8) | 87 | (6.8) | 4.03 (2.52 to 6.44) | <0.0001 | 4.30 (1.88 to 9.83) | 0.0006 | ||
No | Yes | 65 | (20.6) | 97 | (7.5) | 3.42 (2.32 to 5.05) | <0.0001 | 5.32 (2.44 to 11.62) | <0.0001 | ||
Yes | Yes | 17 | (5.4) | 4 | (0.3) | 30.49 (8.68 to 107.02) | <0.0001 | 0.25 | 20.14 (3.08 to 131.60) | 0.002 | 0.89 |
Having no dummy | Small at birth | ||||||||||
No | No | 94 | (30.2) | 608 | (47.4) | 1.00 (ref group) | 1.00 (ref group) | ||||
Yes | No | 135 | (43.4) | 574 | (44.7) | 1.55 (1.12 to 2.15) | 0.009 | 2.30 (1.26 to 4.20) | 0.007 | ||
No | Yes | 28 | (9.0) | 51 | (4.0) | 3.67 (2.09 to 6.45) | <0.0001 | 3.09 (0.98 to 9.71) | 0.054 | ||
Yes | Yes | 54 | (17.4) | 50 | (3.9) | 5.81 (3.53 to 9.57) | <0.0001 | 0.96 | 17.50 (6.14 to 49.86) | <0.0001 | 0.15 |
Found with head covered | Small at birth | ||||||||||
No | No | 182 | (60.5) | 1137 | (89.2) | 1.00 (ref group) | 1.00 (ref group) | ||||
Yes | No | 41 | (13.6) | 37 | (2.9) | 10.48 (5.49 to 20.02) | <0.0001 | 20.11 (7.01 to 57.71) | <0.0001 | ||
No | Yes | 70 | (23.3) | 100 | (7.8) | 4.06 (2.74 to 6.00) | <0.0001 | 5.20 (2.47 to 10.97) | <0.0001 | ||
Yes | Yes | 8 | (2.7) | 1 | (0.1) | 53.99 (5.57 to 523.27) | 0.0006 | 0.84 | 124.38 (2.59 to 5985.45) | 0.01 | 0.93 |
Covered by >10 tog†† | Small at birth | ||||||||||
No | No | 192 | (60.4) | 1094 | (85.1) | 1.00 (ref group) | 1.00 (ref group) | ||||
Yes | No | 41 | (12.9) | 90 | (7.0) | 2.58 (1.63 to 4.08) | <0.0001 | 2.86 (0.99 to 8.23) | 0.052 | ||
No | Yes | 70 | (22.0) | 93 | (7.2) | 3.73 (2.55 to 5.45) | <0.0001 | 5.66 (2.60 to 12.31) | <0.0001 | ||
Yes | Yes | 15 | (4.7) | 8 | (0.6) | 10.11 (3.59 to 28.46) | <0.0001 | 0.93 | 7.47 (0.83 to 67.29) | 0.073 | 0.43 |