Table 3.
A comparison of socio-demographic characteristics between the National NPD sample and children who have completed any ALSPAC questionnaire or clinical assessment
| National NPD KS4 GME samplea | Enrolled in ALSPACb | Odds ratio |
|||
|---|---|---|---|---|---|
| Characteristic | Category | n/n (%) | n/n (%) | OR (95% CI) | P > chi2‡ |
| Child sex | Female | 871 375/1 770 654 (49.21) | 5470/11 008 (49.69) | 1.02 (0.98–1.06) | 0.313 |
| Child ethnicity | White | 1 508 926/1 744 429 (86.50) | 10 505/10 933 (96.09) | 3.85 (3.50–4.24) | <0.001 |
| Low household income | FSMc | 218 033/1 745 353 (12.49) | 682/10 959 (6.22) | 0.46 (0.43–0.50) | <0.001 |
aAll pupils, excluding those in ALSPAC, from English GMEs who sat their KS4 assessments during the same academic years as the ALSPAC cohort (academic years 2007–09).
bAll pupils, from English GMEs, who are from families that have enrolled in ALSPAC by completing an ALSPAC questionnaire or clinical assessment.
cEligible for ‘free school meals’ (FSM), indicating a joint parental income of ≤£16 000.7 ‡Chi-squared test for homogeneity (equal odds).