Average AORs for smoking and maternal alcohol when room sharing and bed sharing with the multiplicative increase in risk due to bed sharing, for infants aged under 3 months and 3 months up to a year
| Age | Risk factors | Room sharing | Bed sharing | Increase when bed sharing | ||||
|---|---|---|---|---|---|---|---|---|
| group | Smoking | Alcohol | AOR | 95% CI | AOR | 95% CI | Multiplier | 95% CI |
| <3 month | No | No | 1 | – | 5.1 | 2.3 to 11.4 | 5.1 | 2.3 to 11.4 |
| Partner | No | 0.7 | 0.5 to 1.1 | 7.8 | 3.6 to 17.2 | 11.2 | 5.0 to 25.1 | |
| Mother | No | 1.3 | 0.8 to 2.2 | 20.3 | 7.4 to 56.4 | 15.2 | 5.3 to 43.4 | |
| Both | No | 2.9 | 2.0 to 4.2 | 21.6 | 11.1 to 42.3 | 7.5 | 3.9 to 14.6 | |
| Both | Yes | 13.7 | 5.5 to 34.4 | 151.0 | 50.2 to 448.4 | 10.8 | 3.0 to 39.2 | |
| 3 months | No | No | 1 | − | 1.0 | 0.3 to 3.1 | 1.0 | 0.3 to 3.1 |
| and over | Partner | No | 1.2 | 0.9 to 1.7 | 3.0 | 1.2 to 7.5 | 2.5 | 1.0 to 6.3 |
| Mother | No | 1.7 | 1.2 to 2.4 | 6.1 | 1.7 to 22.6 | 3.6* | 0.9 to 13.9 | |
| Both | No | 3.0 | 2.3 to 4.0 | 13.7 | 6.1 to 31.0 | 4.6 | 2.0 to 10.3 | |
| Both | Yes | 15.7 | 8.1 to 30.4 | 243.8 | 76.1 to 781.4 | 15.6 | 4.2 to 57.4 | |
*This multiplier is significant at p=0.062.
The AORs are adjusted for all other factors in the table, any drug use by the mother since birth, bottle feeding, sex, whether matched or unmatched, race, birth weight group, mother's age group, number of live births (grouped), mother single and where slept. AOR, Adjusted OR.