Table 2 Early life characteristics and RF in Hertfordshire Cohort Study women (n = 668).
| Frequency | RF +ve cases | Odds ratio (95% CI) | ||
|---|---|---|---|---|
| No (%) | Univariate | Mutually adjusted | ||
| Birth weight (g) | ||||
| <3175 | 279 | 31 (11.1) | 1.0 | 1.0 |
| 3175–3629 | 238 | 28 (11.8) | 1.07 (0.62 to 1.84) | 1.20 (0.68 to 2.10) |
| >3629 | 151 | 20 (13.2) | 1.22 (0.67 to 2.23) | 1.48 (0.79 to 2.77) |
| p = 0.81 on 2df | p = 0.47 on 2df | |||
| Weight at 1 year (g) | ||||
| <9185 | 227 | 20 (8.8) | 1.0 | |
| 9185–9979 | 216 | 29 (13.4) | 1.61 (0.88 to 2.93) | Not included in model |
| >9979 | 225 | 30 (13.3) | 1.59 (0.88 to 2.90) | |
| p = 0.23 on 2df | ||||
| Conditional growth | ||||
| Lowest third | 227 | 25 (11.0) | 1.0 | 1.0 |
| Middle third | 205 | 23 (11.2) | 1.02 (0.56 to 1.86) | 1.02 (0.55 to 1.88) |
| Highest third | 236 | 31 (13.1) | 1.22 (0.70 to 2.14) | 1.14 (0.63 to 2.06) |
| p = 0.74 on 2df | p = 0.89 on 2df | |||
| Social class (III–V v I–IIINM) | ||||
| I–IIINM | 108 | 15 (13.9) | 1.0 | 1.0 |
| IIIM–V | 523 | 60 (11.5) | 0.80 (0.44 to 1.48) | 0.93 (0.50 to 1.73) |
| Missing/unclassified | 37 | 4 (10.8) | 0.75 (0.23 to 2.43) | 1.06 (0.32 to 3.54) |
| p = 0.76 on 2df | p = 0.95 | |||
| Shared bedroom as child* | ||||
| No | 286 | 46 (16.1) | 1.0 | 1.0 |
| Yes | 379 | 32 (8.4) | 0.48 (0.30 to 0.78) | 0.55 (0.32 to 0.95) |
| p = 0.003 | p = 0.03 | |||
| Birth order† | ||||
| 1st | 252 | 39 (15.5) | 1.0 | 1.0 |
| 2nd–4th | 330 | 32 (9.7) | 0.59 (0.36 to 0.97) | 0.65 (0.38 to 1.12) |
| ⩾5th | 85 | 8 (9.4) | 0.57 (0.25 to 1.27) | 0.83 (0.34 to 2.02) |
| p = 0.08 on 2df | p = 0.29 on 2df | |||
*Three results missing; †one result missing.