Table 1.
Sample Demographic Information.
| Variable | Sweep | N with SDQ data at each wave | M | SD |
|---|---|---|---|---|
| Age | Sweep 2 | 8,955 | 3.13 | 0.19 |
| Sweep 3 | 9,371 | 5.21 | 0.24 | |
| Sweep 4 | 9,171 | 7.23 | 0.24 | |
| Sweep 5 | 9,349 | 10.66 | 0.48 | |
| Sweep 6 | 9,076 | 13.76 | 0.45 | |
| Sweep 7 | 8,933 | 16.68 | 0.48 | |
| Category | % | N | ||
| Sex | Sweep 2 | Female | 50.25 | 4,500 |
| Sweep 2 | Male | 49.75 | 4,455 | |
| Sweep 3 | Female | 49.89 | 4,675 | |
| Sweep 3 | Male | 50.11 | 4,696 | |
| Sweep 4 | Female | 50.22 | 4,606 | |
| Sweep 4 | Male | 49.88 | 4,565 | |
| Sweep 5 | Female | 50.41 | 4,713 | |
| Sweep 5 | Male | 49.59 | 4,636 | |
| Sweep 6 | Female | 50.07 | 4,553 | |
| Sweep 6 | Male | 49.93 | 4,523 | |
| Sweep 7 | Female | 50.07 | 4,473 | |
| Sweep 7 | Male | 49.93 | 4,460 | |
| Child ethnicity | White | 82.94 | 7,500 | |
| Other Ethnicity | 17.06 | 1,543 | ||
| Maternal academic qualification | Higher degree | 4.34 | 392 | |
| First degree | 16.67 | 1,506 | ||
| Diplomas in higher education | 9.74 | 880 | ||
| A/AS/S Levels | 10.43 | 942 | ||
| O level/GCSE Grades A-C | 32.44 | 2,931 | ||
| GCSE Grades A-C | 9.05 | 818 | ||
| Other academic qualification | 2.78 | 251 | ||
| None of these qualifications | 14.56 | 1,316 | ||
| Deprivation | Most deprived decile | 12.98 | 1128 | |
| 10% to <20% | 11.78 | 1,023 | ||
| 20% to <30% | 11.18 | 971 | ||
| 30% to <40% | 9.67 | 840 | ||
| 40% to <50% | 9.39 | 816 | ||
| 50% to <60% | 9.01 | 783 | ||
| 60% to <70% | 8.28 | 719 | ||
| 80% to <90% | 9.34 | 811 | ||
| Least deprived decile | 9.96 | 865 |
Note. These are unweighted and based on the sample of participants with Strengths and Difficulties Questionnaire data up to age 17.