title: Correlates of objectively measured sedentary time and self-reported screen time in Canadian children.
abstract: BACKGROUND
  Demographic, family, and home characteristics play an important role in determining childhood sedentary behaviour. The objective of this paper was to identify correlates of total sedentary time (SED) and correlates of self-reported screen time (ST) in Canadian children.
  
  
  METHODS
  Child- and parent-reported household, socio-demographic, behavioural, and diet related data were collected; directly measured anthropometric and accelerometer data were also collected for each child. Participants with complete demographic, anthropometric, and either SED (n=524, 41% boys) or ST (n=567, 42% boys) data from the Canadian site of the International Study of Childhood Obesity Lifestyle and the Environment (ISCOLE) were included in analysis. Sixteen potential correlates of SED and ST were examined using multilevel general linear models, adjusting for sex, ethnicity, number of siblings, and socio-economic status. All explanatory variables moderately associated (p<0.10) with SED and/or ST in univariate analyses were included in the final, fully-adjusted models. Variables that remained significant in the final models (p<0.05) were considered correlates of SED and/or ST.
  
  
  RESULTS
  Children averaged 8.5 hours of daily SED; no differences in total SED, or total ST were seen between girls and boys, but boys reported significantly more video game/computer usage than girls. Boys also had higher waist circumference and BMI z-scores than girls. In the final models, waist circumference and number of TVs in the home were the only common correlates of both SED and ST. SED was also negatively associated with sleep duration. ST was also positively associated with mother's weight status, father's education, and unhealthy eating pattern score and negatively associated with healthy eating pattern score, and weekend breakfast consumption. Few common correlates existed between boys and girls.
  
  
  CONCLUSIONS
  Several factors were identified as correlates of SED and/or of ST in Canadian children; however, few correlates were common for both SED and ST, and for both boys and girls. This suggests that a single strategy to reduce SED and ST is unlikely to be effective. Future work should examine a variety of other, non-screen based sedentary behaviours and their potential correlates in the hopes of creating tailored public health messages to reduce SED and ST in both boys, and girls.
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. alleblanc@cheo.on.ca.|Population Health, Faculty of Graduate and Postdoctoral Studies, University of Ottawa, Ottawa, Ontario, Canada. alleblanc@cheo.on.ca.
authors.forename: Allana G
authors.initials: AG
authors.lastname: LeBlanc
authors.affiliation: Pennington Biomedical Research Center, Baton Rouge, Louisiana, US. stephanie.broyles@pbrc.edu.
authors.forename: Stephanie T
authors.initials: ST
authors.lastname: Broyles
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. jpchaput@cheo.on.ca.|Population Health, Faculty of Graduate and Postdoctoral Studies, University of Ottawa, Ottawa, Ontario, Canada. jpchaput@cheo.on.ca.|Department of Pediatrics, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada. jpchaput@cheo.on.ca.|School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada. jpchaput@cheo.on.ca.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Chaput
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. geled@me.com.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Leduc
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. charlesboyer613@hotmail.com.
authors.forename: Charles
authors.initials: C
authors.lastname: Boyer
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. mborg031@gmail.com.|School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada. mborg031@gmail.com.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Borghese
authors.affiliation: Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada. mtremblay@cheo.on.ca.|Population Health, Faculty of Graduate and Postdoctoral Studies, University of Ottawa, Ottawa, Ontario, Canada. mtremblay@cheo.on.ca.|Department of Pediatrics, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada. mtremblay@cheo.on.ca.|School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada. mtremblay@cheo.on.ca.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Tremblay
mesh_terms: D000328:Adult; D015992:Body Mass Index; D001835:Body Weight; D002170:Canada; D002648:Child; D002652:Child Behavior; D003201:Computers; D004522:Educational Status; D015444:Exercise; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010290:Parents; D063766:Pediatric Obesity / Q000209:etiology; D057185:Sedentary Behavior; D057566:Self Report; D012737:Sex Factors; D012890:Sleep; D013690:Television; D018910:Video Games; D055105:Waist Circumference