TABLE 1.
Basic characteristics of 18 studies included
| First author (year) | Study area, country a | Sample size | Sample age (years, range and/or mean ± SD) b | Sample characteristics (follow‐up status for longitudinal studies) | Statistical model |
|---|---|---|---|---|---|
| Cohort studies | |||||
| Chen (2016) 26 | Arkansas, USA [S] | 21 639 | In 2003–2004 | School children (followed up from academic year 2003/2004 to 2009/2010 with seven repeated measures) | Growth curve model and cox regression |
| Lee (2012) 29 | USA [N] | 7710 | 6.2 ± 0.4 in 1999 | School children (follow up from 1999 to 2004 with four repeated measures and an attrition rate of 43.0%) | Multilevel linear regression |
| Leung (2011) 6 | California, USA [CT4] | 353 | 6–7 in 2005 | Girls (followed up from 2005 to 2008 with three repeated measures and an attrition rate of 20.5%) | Generalized linear and logistic regression |
| Powell (2009) 21 | USA [N] | 5215 | 12–17 (15.5 ± 1.7) in 1997 | Adolescents living at home (followed up from 1997 to 2000 with four repeated measures) | Multilevel linear regression |
| Shier (2016) 24 | USA [N] | 933 | 12–13 in 2013 | Children in military families | Multiple linear regression |
| Sturm (2005) 15 | USA [N] | 13 282 | 6.2 ± 0.4 in 1999 | Elementary school children (followed up from 1999 to 2002 with three repeated measures and an attrition rate of 42.4%) | Multilevel linear regression |
| Zhang (2016) 23 | China [S9] | 348 | 6–17 (10.9 ± 2.8) in 2009 | Followed up from 2009 to 2011 with two repeated measures | Generalized estimating equation |
| Cross‐sectional studies | |||||
| Auld (2009) 20 | USA [N] | 73 041 | 14.7 in 1997–2003 | School children in Grades 8 and 10 | Quantile regression |
| Davis (2009) 27 | California, USA [S] | 529 367 | In 2002–2005 | Middle and high school students | Linear and logistic regression |
| Fiechtner (2013) 28 | Massachusetts, USA [S] | 438 | 2–6.9 in 2006–2009 | Overweight and obese preschool‐age children | Multivariate linear regression |
| Fiechtner (2015) 22 | Massachusetts, USA [S] | 49 770 | 4–18 in 2011–2012 | Paediatric patients | Multivariate linear regression |
| Galvez (2009) 18 | New York, USA [C] | 323 | 6–8 in 2004 | NA | Multivariate logistic regression |
| Gorski Findling (2018) 19 | USA [N] | 3748 | 2–18 in 2012–2013 | NA | Logistic regression |
| Li (2015) 17 | Alabama, USA [S] | 613 | 4–13 in 2013 | Elementary school children | Multilevel regression |
| Mellor (2011) 16 | Virginia, USA [S] | 2023 | 11.4 ± 1.7 in 2006 | Grades 3, 6, and 7 students | Linear and logistic regression |
| Powell (2007) 13 | USA [N] | 73 079 | 14.7 ± 1.2 in 1997–2003 | School children at Grades 8–10 (seven annual repeated measures from 1997 to 2003) | Multilevel linear regression |
| Seliske (2009) 14 | Canada [N] | 7281 | 11–16 in 2005–2006 | Grades 6–10 school children | Multilevel logistic regression |
| Wall (2012) 25 | Minneapolis/St. Paul, USA [C] | 2682 | 14.5 ± 2.0 in 2009–2010 | Public middle and high school students | Multivariate linear regression |
Abbreviation: NA, not available.
a
Study area: [N], national; [S], state (e.g., in the United States) or equivalent unit (e.g., province in China and Canada); [Sn], n states or equivalent units; [CT], county or equivalent unit; [CTn], n counties or equivalent units; [C], city; [Cn], n cities.
b
Sample age: age in baseline year for cohort studies or mean age in survey year for cross‐sectional studies.