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. 2013 Feb 28;2013(2):CD007651. doi: 10.1002/14651858.CD007651.pub2

Jones 2008.

Methods Design: cluster randomized controlled trial 
 Theoretical framework: Transtheoretical Model, Social Cognitive Theory 
 Number of intervention groups: 1 
 Number of control groups: 1 
 Follow‐up: immediately post‐intervention
Participants N (intervention): 291 
 N (control): 315
Age (mean): 11.6 years 
 Sex: female 
 Ethnicity: White
Interventions Country: US 
 Setting: school, unstated if urban or rural 
 Provider: peer, physical education (PE) teachers and other teachers 
 Duration: 1.5 school years 
 Intervention: the IMPACT intervention included 3 major components: 1) a health curriculum for grades 6 and 7 (classroom lessons and behavioral journalism); 2) a PE program; and 3) a school food service component that emphasized calcium‐rich food choices). Peer‐based behavioral journalism involved the use of media (e.g. school‐based newsletter with role model stories). The intervention used a 6th grade health curriculum, including 16 sessions that were implemented during PE classes, 3 times per week. The lessons in this curriculum promoted increased consumption of calcium‐rich foods and increased weight‐bearing physical activities. The curriculum also contained behaviorally based and active lessons adapted to the PE environment. Science‐based lessons were administered during 7th grade science classes. The PE component of the program (i.e. "IMPACTivities") was implemented in the 6th and 7th grades during PE and athletics classes. The classes contained an initial 10‐min warm‐up (i.e. high‐impact activities ‐ rope‐jumping, circuit training, and box‐step activities) 
 Control: the control group participated in the usual health program
Outcomes Duration of physical activity
Television viewing (minutes spent watching television)
Notes  
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) Unclear risk Comment: a computer‐generated random numbers table was used for the randomization process
Allocation concealment (selection bias) Low risk Comment: criterion not applicable because all participants were allocated at 1 point in time following recruitment, so at time of recruitment allocation was not known
Blinding (performance bias and detection bias) 
 All outcomes High risk Comment: no information given, likely not done
Incomplete outcome data (attrition bias) 
 All outcomes High risk Comment: incomplete outcome data was not adequately addressed
Selective reporting (reporting bias) Low risk Comment: all outcomes identified a priori were reported on
Confounders controlled? Low risk Comment: all relevant confounders taken into account
Data collection methods valid and reliable? Low risk Comment: data collection tools reported to be valid and reliable