title: Changing from primary to secondary school highlights opportunities for school environment interventions aiming to increase physical activity and reduce sedentary behaviour: a longitudinal cohort study.
abstract: BACKGROUND
  There is little empirical evidence of the impact of transition from primary to secondary school on obesity-related risk behaviour. The purpose of this study was to examine the effect of a change of school system on physical activity (PA) and sedentary behaviour in pre-early adolescents.
  
  
  METHODS
  Fifteen schools in Victoria, Australia were recruited at random from the bottom two strata of a five level socio-economic scale. In nine schools, students in year 6 primary school transitioned to a different school for year 7 secondary school, while in six schools (combined primary-secondary), students remained in the same school environment from year 6 to year 7. Time 1 (T1) measures were collected from students (N=245) in year 6 (age 11-13). Time 2 (T2) data were collected from 243 (99%) of the original student cohort when in year 7. PA and sedentary behaviour data were collected objectively (via ActiGraph accelerometer) and subjectively (via child self-report recall questionnaire). School environment data were collected via school staff survey. Change of behaviour analyses were conducted longitudinally i) for all students and ii) by change/no change of school. Mixed model regression analysis tested for behavioural interaction effects of changing/not changing school.
  
  
  RESULTS
  Sixty-three percent (N=152) changed schools from T1 to T2. Across all students we observed declines in average daily moderate to vigorous physical activity (MVPA) (-4 min) and light PA (-23 min), and increases in average daily sedentary behaviour (16 min), weekday leisure screen time (17 min) and weekday homework screen time (25 min), all P<0.05. Compared to students who remained in the same school environment, students who changed school reported a greater reduction in PA intensity at recess and lunch, less likelihood to cycle to/from school, greater increase in weekday (41 mins) and weekend (45 mins) leisure screen time (P<0.05) and greater encouragement to participate in sport. School staff surveys identified that sport participation encouragement was greater in primary and combined primary-secondary than secondary schools (P<0.05).
  
  
  CONCLUSIONS
  Transitioning from primary to secondary school negatively impacts on children's PA and sedentary behaviour, and has further compounding effects on behaviour type by changing school environments.
authors.affiliation: WHO Collaborating Centre for Obesity Prevention, Deakin University, Geelong, Australia. mjenn@deakin.edu.au.|School of Health and Social Development, Deakin University, Burwood, Australia. mjenn@deakin.edu.au.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Marks
authors.affiliation: School of Health and Social Development, Deakin University, Burwood, Australia. lisa.barnett@deakin.edu.au.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Barnett
authors.affiliation: WHO Collaborating Centre for Obesity Prevention, Deakin University, Geelong, Australia. claudia.strugnell@deakin.edu.au.
authors.forename: Claudia
authors.initials: C
authors.lastname: Strugnell
authors.affiliation: WHO Collaborating Centre for Obesity Prevention, Deakin University, Geelong, Australia. steven.allender@deakin.edu.au.|School of Health and Social Development, Deakin University, Burwood, Australia. steven.allender@deakin.edu.au.
authors.forename: Steven
authors.initials: S
authors.lastname: Allender
mesh_terms: D000293:Adolescent; D001315:Australia; D002648:Child; D015331:Cohort Studies; D004777:Environment; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D012574:Schools; D057185:Sedentary Behavior; D012959:Socioeconomic Factors; D013334:Students