Table 1.
Descriptive characteristics of participants (mean ± SD or n (%)).
| Included in analyses | Excluded from analysesb | p (ttest/χ2) | |
|---|---|---|---|
| Demographic characteristics | |||
| male | 1270 (52) | 604 (49) | 0.170 |
| Age | 11.99 ± 0.38 | 12.04 ± 0.44 | 0.007 |
| SEP z-score | 0.22 ± 0.98 | 0.07 ± 1.00 | 0.002 |
| Pubertal status | |||
| Pre-pubertal | 124 (10) | 41 (9) | 0.330 |
| Early pubertal | 323 (25) | 122 (26) | |
| Mid-pubertal | 654 (52) | 231 (50) | |
| Late pubertal | 165 (13) | 64 (14) | |
| Post-pubertal | 4 (0.3) | 5 (1.0) | |
| Movement behaviors (self-report, min/day) | |||
| MVPA | 121 ±78 | 115 ± 71 | 0.120 |
| Sleep | 600 ± 63 | 596 ± 62 | 0.180 |
| Screen time | 186 ± 116 | 203 ± 115 | 0.006 |
| Movement behaviors (accelerometry, min/day) | |||
| MVPA | 63 ± 35 | 59 ± 35 | 0.030 |
| Sleep | 567 ± 47 | 564 ± 64 | 0.320 |
| Academic outcomes | |||
| Literacya | 556 ± 61 | 541 ± 60 | 0.004 |
| Numeracy | 576 ± 70 | 557 ± 59 | 0.001 |
Notes: Due to rounding some percentages add up to >100%. Bold text denotes p < 0.05.
a
Literacy score was calculated as the arithmetic mean of language, reading, writing, and spelling scores.
b
n does not always add up to 604 due to missing data. Abbreviations: MVPA = moderate-to-vigorous intensity physical activity; SEP = socioeconomic position.