| Number of studies | Study enrollmenta | Study retentionb | Average retention rates |
---|---|---|---|---|
Race or ethnicity | ||||
 Hispanic | 5 | 586 | 511 | 82.8 |
 African American | 10 | 1331 | 1059 | 83.5 |
 African American, white and other | 8 | 1927 | 1763 | 92.1 |
Intervention target | ||||
 Children | 3 | 413 | 388 | 91.1 |
 Children and parent | 20 | 3431 | 2945 | 85.6 |
Body weight status | ||||
 Overweight or obese | 9 | 1581 | 1314 | 79.6 |
 All weights | 10 | 1523 | 1334 | 90.0 |
 Body weight status not measured | 4 | 740 | 685 | 92.6 |
Study type | ||||
 Prevention | 10 | 1523 | 1334 | 90.0 |
 Treatment | 13 | 2321 | 1999 | 83.6 |
Intervention length | ||||
 <1 year | 16 | 1658 | 1461 | 88.6 |
 ≥1 year | 7 | 2186 | 1872 | 81.1 |
Study type and treatment length | ||||
 Prevention <1 year | 7 | 707 | 614 | 90.4 |
 Prevention ≥1 year | 3 | 816 | 720 | 88.8 |
 Treatment <1 year | 9 | 951 | 847 | 87.2 |
 Treatment ≥1 year | 4 | 1073 | 873 | 74.0 |
Primary outcome | ||||
 BMI or anthropometrics | 10 | 2342 | 2026 | 82.9 |
 Other (behavior, physiology, etc.) | 13 | 1502 | 1307 | 89.0 |
Intervention settingc | ||||
 School | 5 | 1273 | 1151 | 91.7 |
 Home or community | 15 | 2410 | 2051 | 85.5 |
 Laboratory | 2 | 126 | 102 | 81.1 |
Main intervention group | ||||
 Nutrition or physical activity | 4 | 755 | 712 | 92.8 |
 Nutrition and physical activity | 19 | 3089 | 2621 | 85.0 |
Study design | ||||
 Randomized controlled trial | 19 | 2739 | 2440 | 89.3 |
 Cluster randomized controlled trial | 2 | 745 | 656 | 75.6 |
 Controlled trial | 1 | 235 | 136 | 57.9 |
 Trial without control | 1 | 125 | 101 | 80.8 |
Mean age of childrend | ||||
 <12 years | 15 | 2708 | 2333 | 86.2 |
 ≥12 years | 8 | 1136 | 1000 | 86.7 |
Number of intervention sessionse | ||||
 ≤12 | 7 | 752 | 636 | 86.3 |
 ≥13 | 15 | 2840 | 2445 | 85.5 |
Sample size | ||||
 <100 | 9 | 493 | 435 | 86.9 |
 ≥100 | 14 | 3351 | 2898 | 86.0 |