Melnyk 2013.

Study characteristics
Methods	Study design: cluster‐RCT
Participants	School inclusion criteria: 11 high schools from 2 school districts in the southwestern USA. The choice of schools was designed to provide diversity across race or ethnicity as well as socioeconomic status School exclusion criteria: — Student inclusion criteria: teens 14 to 16 years of age enrolled in a health class at 1 of 11 participating high schools, assented to participation, had a custodial parent who consented to the teen's participation in the study and optionally for himself or herself, could speak and read in English, parents could speak and read either Spanish or English Student exclusion criteria: a medical condition that would prevent participation in the PA component of the programme Setting: school Age group: adolescents Gender distribution: females and males Country/Countries where trial was performed: USA
Interventions	Intervention: goal‐setting to promote engagement in healthy lifestyle behaviours and problem‐solving for typical adolescent challenges; educational content to increase teens' knowledge of how to lead a healthy lifestyle; homework to reinforce skills learned in the classroom; 20 minutes of PA within each of the 15 Creating Opportunities for Personal Empowerment components. Teachers chose types of physical activities, which commonly included movement within the classroom, brisk walking, dodge ball, kickball, obstacle courses, "Tank" (a game suggested by the research team), and basketball Comparator: Healthy Teens attention control curriculum was intended to promote knowledge of common adolescent health topics and health literacy. Content included pertinent health information for teens Duration of intervention: 15 weeks Duration of follow‐up: 10 months Number of schools: 11 Theoretical framework: cognitive‐behavioural theory
Outcomes	BMI
Study registration	NCT01704768
Publication details	Language of publication: English Funding: non‐commercial funding (governmental organisation) Publication status: peer‐reviewed journal
Stated aim for study	"The purpose of this study is to test the short and more long‐term efficacy of the Creating Opportunities for Personal Empowerment Healthy Lifestyles Thinking, Emotions, Exercise, Nutrition intervention, versus an attention control program (Healthy Teens) on the healthy lifestyle behaviours, BMI and BMI percentile, social skills, depressive or anxiety symptoms and academic performance of 779 culturally diverse high school teens enrolled in the southwest region of the USA for the ultimate purpose of preventing overweight or obesity, mental health disorders and poor academic functioning"
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: drawing names from a hat
Allocation concealment (selection bias)	Low risk	Comment: allocation could not be predetermined
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Comment: students and teachers were blinded to intervention
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Comment: outcome assessors were blinded [author communication]
Incomplete outcome data (attrition bias) Anthropometrics, Fitness	High risk	Comment: large loss to follow‐up; no description of handling missing data
Incomplete outcome data (attrition bias) Physical activity and sedentary time	High risk	Comment: large loss to follow‐up, no description of handling missing data
Selective reporting (reporting bias)	Low risk	Comment: all specified outcomes reported on
Cluster RCT ‐ Recruitment bias	Low risk	Comment: students blinded to group allocation
Cluster RCT ‐ Baseline imbalance	Low risk	Comment: baseline differences adjusted for
Cluster RCT ‐ Loss of clusters	Low risk	Comment: no clusters lost to follow‐up [author communication]
Cluster RCT ‐ Incorrect analysis	Low risk	Comment: clustering was accounted for in analysis as per protocol paper [author communication]