Melnyk 2013.

Study characteristics
Methods	Study name: COPE (Creating opportunities for personal empowerment) Study design: cluster‐RCT Intervention period: 15 weeks Follow‐up period (post‐intervention): 6 months Differences in baseline characteristics: reported Reliable outcomes: reported Protection against contamination: reported Unit of allocation: school Unit of analysis: individual not accounting for clustering
Participants	N (control baseline) = 433 N (control follow‐up) = 341 N (intervention baseline) = 374 N (intervention follow‐up) = 286 Setting (and number by study group): 11 high schools in 2 school districts Recruitment: research team members introduced the study to all students in each participating health class and sent consent/assent packets home with those teens who expressed interest in study participation Geographic region: southwest USA Percentage of eligible population enrolled: 52% participants Mean age: intervention: 14.75 ± 0.76; control: 14.74 ± 0.70 Sex: intervention: 49.2% female; control: 54.5% female
Interventions	To test the short‐ and longer‐term efficacy of the COPE healthy lifestyles TEEN (Thinking, Emotions, Exercise, Nutrition) programme (referred to here as COPE), vs an attention control programme (Healthy teens), on the healthy lifestyle behaviours, BMI, psychosocial outcomes, social skills, and academic performance of high school adolescents aged 14–16 years Intervention: the COPE programme is a manualised 15‐session educational and cognitive–behavioural skills‐building programme guided by cognitive theory, with PA as a component of each session. The COPE intervention was pilot‐tested 3 times with white, Hispanic, and African‐American adolescents as a group intervention in high school settings. Each session of COPE contains 15–20 min of PA (e.g. walking, dancing, kick‐boxing movements), not intended as an exercise training programme, but rather to build beliefs in the teens that they can engage in and sustain some level of PA on a regular basis. Teens received a COPE manual with homework activities for each of the 15 sessions that reinforced the content and skills in the programme. A parent newsletter describing the content of the COPE programme also was sent home with the teens 4 times during the course of the 15‐week programme, and the teens were instructed to review each newsletter with their parent(s) as part of their homework assignments. Control: the Healthy Teens programme was designed as a 15‐week attention control programme to control for the time the health teachers in the COPE group spent delivering the experimental content to their students. Health teachers received a full‐day training workshop on the Healthy teens content. The content was manualised and focused on safety and common health topics/issues for teens, such as road safety, dental care, infectious diseases, immunisations, and skin care. Control teens also received a manual with homework assignments each week that focused on the topics being covered in class and were asked to review with his or her parent a newsletter that was sent home with the teens 4 times during the programme. The control programme was administered in a format like that of the COPE intervention and included the same number and length of sessions as the experimental programme, but there was no overlap of content between the two programmes. Diet and PA intervention vs control
Outcomes	Outcome measures Primary outcome: BMI, PA Secondary outcomes: depressive and anxiety symptoms, social skills, substance use, and academic performance Process evaluation: reported (fidelity)
Implementation‐related factors	Theoretical basis: Cognitive theory Resources for intervention implementation: reported Who delivered the intervention: reported PROGRESS categories assessed at baseline: gender, race/ethnicity PROGRESS categories analysed at outcome: NR Outcomes relating to harms/unintended effects: depressive and anxiety symptoms Intervention included strategies to address diversity or disadvantage: NR Economic evaluation: NR
Notes	NCT01704768 Funding: this study was funded by the NIH/ National Institute of Nursing Research 1R01NR012171. The study team observed incidents of decreased fidelity to the intervention that occurred at least once, in approximately half of the classrooms.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Random assignment, no further details
Allocation concealment (selection bias)	Unclear risk	Random assignment, no further details
Blinding (performance bias and detection bias) All outcomes	Low risk	States blinded, but not who
Incomplete outcome data (attrition bias) All outcomes	Low risk	Retention was 76% in intervention group at 6 months and 78% in control at 6 months; analyses were performed using all available data (i.e. ITT), including participants who subsequently dropped out of the study.
Selective reporting (reporting bias)	Low risk	Protocol/trial registration document seen. All outcomes reported
Other bias	Low risk	No additional threats to validity
Other bias‐ timing of recruitment of clusters	Low risk	Figure shows recruitment happened prior to randomisation