Univariate and multiple logistic regression analyses predicting PAL callers
| Univariate model | P-value | Multivariate model | P value | |
| OR* (95% CI) | OR* (95% CI) | |||
| Sex | ||||
| Male | 1.0 (0.8 to 1.4) | 0.9 | ||
| First-time parent | ||||
| Yes | 1.5 (1.2 to 2.1) | 0.003 | 1.4 (1.1 to 1.9) | 0.02 |
| Number of siblings | ||||
| 0 | Reference | Reference | ||
| 1 | 0.8 (0.6 to 1.1) | 0.1 | ||
| 2 | 0.4 (0.2 to 0.7) | 0.002 | ||
| 3 | 0.5 (0.2 to 1.4) | 0.2 | ||
| 4 | 0.3 (0.04 to 2.4) | 0.3 | ||
| 5 | 0.4 (0.05 to 3.2) | 0.4 | ||
| Birth method | ||||
| Vaginal | 1.1 (0.8 to 1.4) | 0.7 | ||
| Gestational age | ||||
| Weeks | 1.1 (1.0 to 1.2) | 0.08 | ||
| IVF or sperm/egg donor | ||||
| Yes | 3.9 (1.5 to 9.9) | 0.005† | ||
| Birth weight | ||||
| <2500 g | 0.8 (0.3 to 1.8) | 0.5 | ||
| Birth weight (kg) | 1.2 (0.9 to 1.6) | 0.2 | ||
| Maternal age at delivery | ||||
| Years | 1.0 (1.0 to 1.1) | 0.06 | ||
| Mother’s birthplace | ||||
| Australia | 1.1 (0.8 to 1.5) | 0.7 | ||
| Maternal education | ||||
| No education/up to year 10 | Reference | Reference | Reference | |
| Year 12/trade | 1.7 (0.7 to 4.6) | 0.3 | 1.7 (0.6 to 4.5) | 0.3 |
| University | 3.6 (1.4 to 9.0) | 0.007 | 3.3 (1.3 to 8.4) | 0.01 |
| Breast fed | ||||
| Yes | 4.4 (1.1 to 18.6) | 0.04 | ||
| Received BCG | ||||
| Yes | 1.1 (0.8 to 1.5) | 0.5 |
*OR calculated using logistic regression method.
†IVF was not included in the multivariate analysis due to missing data resulting in loss of statistical power.
PAL, paediatric advice line.