|  | Mean (SD) or percentages | |
---|---|---|---|
 | Use in analysis | T0 | T1 |
Demographic and biological variables | |||
 Sex | % boys | 53.8 | 51.9 |
 Age | years | 3.9 (0.7) | 4.9 (0.7) |
 Birth weight | grams (per 100 g) | 3290 (570) | 3280 (530) |
 Chronic health condition | % with chronic health condition | 7.5 | 7.1 |
 BMIa | % overweight or obese | 24.1 | 18.5 |
 Gross motor skillsa | Composite z-score | 0.0 (1.0) | 0.1 (1.1) |
 Siblings | % having older siblings | 43.2 | 44.5 |
 Parental BMI | % at least one overweight or obese parent | 52.2 | 52.5 |
 SES | Range 16–90; increases with higher SES | 63.1 (15.5) | 62.7 (15.6) |
 Family structure | % single parent households | 10.4 | 9.8 |
Psychological, cognitive and emotional variables | |||
 Self-regulationa | Range 0-30; increases with better self-regulation | 19.2 (9.5) | 23.3 (8.0) |
 Psychological difficulties | Range 0-40; increases with more difficulties | 8.8 (4.3) | 8.5 (4.7) |
 Emotionality temperament | Range 1-5; increases with more pronounced trait | 2.8 (0.7) | 2.8 (0.7) |
 Activity temperament | Range 1-5; increases with more pronounced trait | 3.8 (0.7) | 3.7 (0.7) |
 Shyness temperament | Range 1-5; increases with more pronounced trait | 2.4 (0.7) | 2.4 (0.7) |
 Parenting stress | Range 5-90; increases with more parenting stress | 37.5 (7.5) | 37.6 (7.6) |
 Cognitive performancea | Composite z-score | 0.0 (1.0) | 0.1 (0.9) |
Behavioral variables | |||
 Sleep duration | Hours | 10.8 (0.6) | 10.8 (0.5) |
 Play frequency | % more than once/week | 91.2 | 93.1 |
Social and cultural variables | |||
 Parental sedentary behavior | Hours | 2.8 [2.0, 4.5]b | 3.0 [2.0, 5.0]b |
 Parental sports club membership | % at least one parent is member | 32.0 | 32.8 |
 Parental physical activity | % at least one parent is active | 63.4 | 61.6 |
 Parental Involvement in child physical activity | % at least one parent is involved | 65.0 | 52.3 |
 Mode of transport to childcare | % active | 40.7 | 48.1 |
 Parental tobacco use | % at least one parent smokes | 24.1 | 24.4 |
 Parental alcohol consumption | % at least one parent consumes large amounts | 5.5 | 4.5 |
Environmental variables | |||
 Time outdoors | Hours | 2.0 [1.5, 3.0]b | 2.0 [1.5, 3.0]b |
 Fixed toys | Range 0-7 | 1.6 (1.5) | 1.6 (1.6) |
 Portable toys | Range 0-8 | 4.5 (1.5) | 4.3 (1.5) |
 Days at childcare | Range 0-5 | 2.8 (1.2) | 2.5 (1.3) |
 Living area per person | m2 | 30.8 (9.1) | 30.8 (8.9) |
 Neighborhood safety | Range 0-44; increases with increasing concerns | 12.6 (7.0) | 12.4 (7.2) |
 Dog | % dog owner | 6.9 | 5.5 |
 Season | % spring and fall months | 75.3 | 77.9 |
 Region | % urban | 34.9 | 39.4 |