Table 3.
Risk factors and confounders in the three samples considered for the analysis
| Sample with complete data (n=5,852) | Sample with 3 or more bedwetting measures (n=8,769) | Sample with at least one bedwetting measure (n=10,820) | |
|---|---|---|---|
| Risk factors | |||
| Male gender | 2960 (50.6%) | 4513 (54.1%) | 5586 (51.6%) |
| Child development at 18 months | |||
| Communication | 7.3 (2.4) | 7.3 (2.4) | 7.3 (2.4) |
| Gross motor skills | 9.4 (1.5) | 9.4 (1.6) | 9.4 (1.6) |
| Social skills | 8.2 (2.2) | 8.2 (2.2) | 8.21(2.2) |
| Fine motor skills | 12.9 (1.7) | 12.8 (1.7) | 12.8 (1.8) |
| Parental history of wetting | |||
| Maternal | 471 (8.6%) | 729 (9.1%) | 924 (9.5%) |
| Paternal | 386 (9.4%) | 572 (9.9%) | 684 (10.0%) |
| Gestational length | |||
| <32 weeks | 42 (0.7%) | 84 (1.0%) | 113 (1.0%) |
| < 37 weeks | 274 (4.7%) | 460 (5.3%) | 614 (5.7%) |
| ≥42 weeks | 430 (7.4%) | 640 (7.3%) | 800 (7.4%) |
| Birth weight | |||
| <1500g | 93 (1.6%) | 153 (1.7%) | 191 (1.8%) |
| <2500g | 309 (5.3%) | 496 (5.7%) | 643 (5.9%) |
| ≥4500g | 105 (1.8%) | 164 (1.9%) | 204 (1.9%) |
| Confounders | |||
| Manual social class | 706 (12.8%) | 1239 (15.4%) | 1663 (15.4%) |
| Early parenthood | 213 (3.6%) | 419 (4.8%) | 648 (6.0%) |
| Housing inadequacy | 408 (7.0%) | 748 (8.6%) | 983 (9.3%) |
| Low maternal education | 580 (10.0%) | 996 (11.6%) | 1343 (12.9%) |
| Financial difficulties | 803 (13.9%) | 1297 (15.1%) | 1653 (16.0%) |
| Family size>=3 | 251 (4.3%) | 424 (4.9%) | 600 (5.8%) |
| Poor social network | 716 (12.3%) | 1130 (13.0%) | 1434 (13.6%) |
n (%) for categorical variable or mean (SD) for continuous variables
Actual number with available data on each risk factor varies in each of the samples shown here.
Manual social class includes manual and part/unskilled.