Table 2 Main characteristics of the studies included in the systematic review
Main characteristics | n articles (%) |
|---|---|
Sample size | |
< 500 or not reported | 46 (56.8) |
≥ 500 < 1000 | 15 (18.5) |
≥ 1000 | 20 (24.7) |
Age group (articles can be included in more than one age category) | |
3 to 7 years | 22 (27.2) |
8 to 12 years | 39 (48.1) |
13 to 18 years | 64 (79.0) |
Study design | |
Cross-sectional study | 64 (79.0) |
Prospective cohort study | 17 (21.0) |
Details on dietary assessment | |
Dietary assessment method | |
FFQ | 31 (38.3) |
24 h recall | 30 (37.0) |
Dietary record | 9 (11.1) |
Combination of two methods | 7 (8.6) |
Other | 4 (5.0) |
Frequency of dietary assessments | |
Once | 40 (49.4) |
Twice | 28 (34.6) |
Three times or more | 13 (16.0) |
Validity of dietary assessment (as reported by the authors) | |
Yes | 31 (38.3) |
No | 10 (12.3) |
Unknown | 40 (49.4) |
Adults’ involvement in dietary assessment | |
All studies | 35 of 81(43.2) |
Studies with children aged 3–7 years | 17 of 22 (77.2) |
Studies with children aged 8–11 years | 21 of 39 (53.8) |
Studies with children aged 12–18 years | 17 of 64 (26.6) |
Study quality | |
Low | 47 (58.0) |
Moderate | 31 (38.3) |
High | 3 (3.7) |