Table 1. Descriptive statistics for the longitudinal samples.
F = number of females in the sample, M = mean, SD = standard deviation; LCBC = Lifespan Changes in Brain and Cognition; ABCD = Adolescent Brain Cognitive Development; UKB = UK Biobank. Numbers are given in years for baseline age, time since baseline, and education, birth weight is given in kilograms. For LCBC, only 584 participants had information on education. Parental education was used in ABCD, and in LCBC when the participant was below 18 y of age, and also if no other education information was available for participants up to 21 y.
| Study | N | F | Scans | Baseline age | Time since baseline | Birth weight | Education | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| M | SD | Range | M | SD | Range | M | SD | Range | M | SD | Range | ||||
| LCBC | 635 | 350 | 1922 | 19.1 | 20.7 | 4.1–81.9 | 2.6 | 2.4 | 0.1–8.3 | 3.5 | 0.6 | 0.9–6.0 | 17.1 | 2.4 | 9–24 |
| ABCD | 3324 | 1562 | 6648 | 10.0 | 0.6 | 8.9–11.1 | 2.0 | 0.1 | 1.4–2.8 | 3.2 | 0.7 | 1.0–6.7 | 16.0 | 2.6 | 6–21 |
| UKB | 1759 | 1009 | 3518 | 62.0 | 7.1 | 47–80.3 | 2.3 | 0.1 | 2.0–2.9 | 3.4 | 0.6 | 0.9–6.4 | 14.2 | 2.4 | 7–16 |