Table 3.
Demographic information of the study sample at baseline and follow-up
| Variable | Baseline (T1) Mean (SD) or n (%) |
Total n | Follow-up (T2) Mean (SD) or n (%) |
Total n |
|---|---|---|---|---|
| Schools enrolled | 36 | 11 | ||
| Age in years | 13.56 (1.36) | 7412 | 13.53 (1.23) | |
| Gender | 7377 | 2619 | ||
| Female | 4050 (54.9%) | 1623 (62.0%) | ||
| Male | 3015 (40.9%) | 876 (33.4%) | ||
| Prefer to self-identify | 159 (2.2%) | 74 (2.8%) | ||
| Other | 153 (2.1%) | 46 (1.8%) | ||
| Ethnicity | 7404 | 2625 | ||
| White | 4497 (60.7%) | 1306 (49.8%) | ||
| Black/African/Caribbean/Black British | 1405 (19.0%) | 638 (24.3%) | ||
| Asian/Asian British | 586 (7.9%) | 289 (11.0%) | ||
| Mixed heritage | 563 (7.6%) | 244 (9.3%) | ||
| Other | 353 (4.8%) | 148 (5.6%) | ||
| Year group | 7407 | 2631 | ||
|
Year 7 Age (in years) |
1215 (16.4%) 11.76 (0.62) |
397 (15.1%) 11.85 (0.52) |
||
|
Year 8 Age (in years) |
1703 (23.0%) 12.70 (0.57) |
685 (26.0%) 12.75 (0.54) |
||
|
Year 9 Age (in years) |
2224 (30.0%) 13.69 (0.52) |
860 (32.7%) 13.80 (0.49) |
||
|
Year 10 Age (in years) |
1631 (22.0%) 14.68 (0.49) |
604 (23.0%) 14.79 (0.47) |
||
|
Year 11 or above Age (in years) |
634 (8.6%) 15.97 (1.05) |
85 (3.2%) 16.19 (1.44) |