title: Physical activity, screen time and self-rated health and mental health in Canadian adolescents.
abstract: OBJECTIVE
  Physical activity (PA) and screen time (ST) are associated with self-rated health (SRH) in adults; however, SRH has been less studied among youth, and information about self-rated mental health (SRMH) is lacking. This study examined the associations of PA and ST with SRH and SRMH among adolescents.
  
  
  METHODS
  Cross-sectional data from the 2011-2012 Canadian Community Health Survey included 7725 participants aged 12-17years, representing 1,820,560 Canadian adolescents. Associations of self-reported PA and ST to SRH and SRMH were assessed, controlling for age, race/ethnicity, smoking, highest household education and weight status.
  
  
  RESULTS
  Excellent/very good SRH was reported by 78% of active vs. 62% of inactive adolescents, and 77% of those meeting vs. 70% of those exceeding ST guidelines (both p<0.001). Excellent/very good SRMH was reported by 81% of active vs. 76% of inactive adolescents, and 84% of those meeting vs. 78% of those exceeding ST guidelines (both p<0.001). Inactive adolescents had twice higher odds of sub-optimal SRH, and inactive girls had 30% greater odds of sub-optimal SRMH. Adolescents exceeding 2h/day ST had 30% greater odds of sub-optimal SRH, and 30-50% greater odds of sub-optimal SRMH.
  
  
  CONCLUSIONS
  PA and ST are independently associated with health perceptions among Canadian adolescents. Interventions should consider health perceptions in addition to biomedical outcomes.
authors: Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK, Canada. Electronic address: katya.herman@uregina.ca.
authors: Katya M
authors: KM
authors: Herman
authors: Department of Public Health Sciences, Queen's University, Kingston, ON, Canada; Clinical Research Centre, Kingston General Hospital, Kingston, Canada. Electronic address: hopmanw@kgh.kari.net.
authors: Wilma M
authors: WM
authors: Hopman
authors: Faculty of Kinesiology & Physical Education, University of Toronto, Toronto, Canada. Electronic address: catherine.sabiston@utoronto.ca.
authors: Catherine M
authors: CM
authors: Sabiston
mesh_terms: D000293:Adolescent; D002170:Canada / Q000453:epidemiology; D002648:Child; D003201:Computers / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008603:Mental Health / Q000706:statistics & numerical data; D009043:Motor Activity; D057185:Sedentary Behavior; D012647:Self-Assessment; D013690:Television / Q000706:statistics & numerical data
keywords: Children; Exercise; Perceived health; Quality of life; Sedentary behaviour