Adab 2018.

Study characteristics
Methods	Study design: cluster‐RCT
Participants	School inclusion criteria: all state primary schools in the West Midlands (UK), which included school years 1 to 5 (children aged 5 to 10 years) and were within a 35‐mile radius of the University of Birmingham School exclusion criteria: schools with fewer than 17 pupils in the relevant year group (minimum cluster size) or those who were in special measures (status applied by the Office for Standards in Education when it considers that a school fails to supply an acceptable level of education and appears to lack the leadership capacity necessary to secure improvements) Student inclusion criteria: all Year 1 pupils (aged 5 to 6 years) in participating schools Student exclusion criteria: — Setting: school Age group: children Gender distribution: females and males Country where trial was performed: UK
Interventions	Intervention: 4 overlapping components 30 minutes of additional MVPA on each school day—at least 15 minutes to be outside of break times Term cooking workshops during school time, which parents were invited to attend to participate with their child and that were preceded by short classroom sessions for the children 6‐week programme (Villa Vitality) developed to encourage healthy eating and increase PA and delivered by staff from an iconic sporting institution. School classes spent 2 days undertaking activities (indoor‐based movement routines, use of dance mats, ball skills session, interactive nutritional sessions, and opportunity to practise cooking skills) at an English premier league football club, separated by a 6‐week period during which teachers were asked to spend curriculum time working on a class project and involving children and their parents with weekly health challenges Information sheets sign posting children and their families on ways to be active over the summer (identical for all schools) and PA opportunities in their local area (school‐specific sheets produced by the study team and checked before distribution by the school) Comparator: continued with ongoing Year 2 health‐related activities plus citizenship education resources, excluding topics related to healthy eating and PA Duration of intervention: 12 months Duration of follow‐up: 15 and 18 months Number of schools: 54 Theoretical framework: —
Outcomes	PA participation PA duration Sedentary time BMI Health‐related quality of life
Study registration	ISRCTN97000586
Publication details	Language of publication: English Funding: non‐commercial funding (governmental organisation) Publication status: peer‐reviewed journal
Stated aim for study	"The main aim is to assess the clinical and cost‐effectiveness of the 12‐month childhood obesity prevention intervention programme, developed and refined in the Birmingham healthy Eating and Active lifestyle for CHildren Study, using usual practice in primary schools as the comparator"
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote from publication: "a blocked balancing algorithm was used to randomise participating schools to intervention or comparator arms. Schools were randomly allocated according to a randomisation scheme, which minimized imbalance on several characteristics"
Allocation concealment (selection bias)	Low risk	Quote from publication: "to ensure concealment of allocation we carried out randomisation after baseline measurements. Sessional researchers blind to arm allocation mainly undertook further data collection"
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: participants not blinded
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote from publication: "researchers blind to arm allocation mainly undertook further data collection"
Incomplete outcome data (attrition bias) Anthropometrics, Fitness	Low risk	Comment: most loss to follow‐up due to children changing schools
Incomplete outcome data (attrition bias) Physical activity and sedentary time	Low risk	Comment: most loss to follow‐up due to children changing schools
Selective reporting (reporting bias)	Low risk	Comment: protocol published; all stated outcomes reported
Cluster RCT ‐ Recruitment bias	Low risk	Comment: schools and participants recruited before randomisation
Cluster RCT ‐ Baseline imbalance	Low risk	Comment: clusters balanced at baseline
Cluster RCT ‐ Loss of clusters	Low risk	Quote from publication: 1 school lost at first follow‐up (N = 20 students) but retained in analysis
Cluster RCT ‐ Incorrect analysis	Low risk	Quote from publication: "adjusted model included the baseline measurement and treatment arm as the independent variables, and to account for the clustered nature of the sample, school as the random effect"