Table 4 Reported intra-cluster correlation coefficients for primary outcomes (N = 26)
Author | Year | Cluster unit | Outcome | Health area | Outcome type | ICC estimate |
|---|---|---|---|---|---|---|
Stallard [53] | 2012 | year group | Symptoms of low mood (depression) | socioemotional function | continuous | 0.012 |
Chisholm [22] | 2016 | class | Stigma of mental illness | socioemotional function | continuous | 0.1 |
Obsuth [71] | 2017 | school | School exclusion | socioemotional function | binary | 0.028 |
Connolly [82] | 2018 | school | Prosocial behaviour | socioemotional function | continuous | 0.116 |
Ford [32] | 2019 | school | Mental health / behaviour | socioemotional function | continuous | 0.121 |
Axford [44] | 2020 | school | Victimisation (being bullied) occurring at least twice a month in the last 2 months | socioemotional function | binary | 0.019 |
Campbell [26] | 2008 | school | Smoking in the past week | smoking | binary | 0.017 |
Conner [74] | 2019 | school | Ever smoking | smoking | binary | 0.017 |
McKay [24] | 2018 | school | Heavy episodic drinking in the previous 30 days (> = 6 units for males and > = 4.5 units for females) | alcohol misuse | binary | 0.121 |
Croker [40] | 2012 | school | Child's eating habits | obesity | continuous | 0.07 |
Fairclough [56] | 2013 | school | Waist circumference (cm) | obesity | continuous | 0.06 |
Lloyd [57] | 2018 | school | BMI z score | obesity | continuous | 0.014 |
Breheny [43] | 2020 | school | BMI z-score at 12 months | obesity | continuous | 0.001 |
Jago [41] | 2015 | school | Mean weekday minutes of moderate to vigorous physical activity per day | physical activity | continuous | 0.0005 |
Harrington [58] | 2018 | school | Minutes per day of moderate- to vigorous physical activity | physical activity | continuous | 0.02 |
Norris [67] | 2018 | school | Sedentary behaviour during the school day in minutes | physical activity | continuous | 0.080 |
Jamesa [28] | 2004 | class | Consumption of carbonated drinks over 3 days (in glasses) | nutrition | continuous | -0.009 |
Christian [25] | 2014 | school | Combined daily fruit and vegetable intake (grams per day) | nutrition | continuous | 0.003 |
Redmond [81] | 1999 | school | Proportion of teeth sites with caries at 6 months | dental health | continuous | 0.16 |
Worthington [31] | 2001 | school | Plaque score | dental health | continuous | 0.023 |
Milsom [59] | 2006 | school | Whether the child has active caries in their first permanent molars | dental health | binary | 0.027 |
Mulvaney [68] | 2006 | school | Use of visibility aid (reflective and fluorescent slap wrap) while cycling | injury | binary | 0.21 |
Kendrick [79] | 2007 | school | Knowledge score for fire and burn prevention | safety | continuous | 0.187 |
Hubbard [76] | 2016 | school | Number of recognised cancer warning signs | cancer | continuous | 0.038 |
Henderson [27] | 2007 | school | Terminations of pregnancy by age 20 | obstetrics | count | 0.005 |
Giles [23] | 2014 | school | Intention to breastfeed | obstetrics | continuous | 0.12 |