title: Brief scales to assess physical activity and sedentary equipment in the home.
abstract: BACKGROUND
  Sedentary behaviors such as TV viewing are associated with childhood obesity, while physical activity promotes healthy weight. The role of the home environment in shaping these behaviors among youth is poorly understood. The study purpose was to examine the reliability of brief parental proxy-report and adolescent self-report measures of electronic equipment and physical activity equipment in the home and to assess the construct validity of these scales by examining their relationship to physical activity, sedentary behavior, and weight status of children and adolescents.
  
  
  METHODS
  Participants were adolescents (n = 189; mean age = 14.6), parents of adolescents (n = 171; mean age = 45.0), and parents of younger children (n = 116; parents mean age = 39.6; children's mean age = 8.3) who completed two surveys approximately one month apart. Measures included a 21-item electronic equipment scale (to assess sedentary behavior facilitators in the home, in the child or adolescent's bedroom, and portable electronics) and a 14-item home physical activity equipment scale. Home environment factors were examined as correlates of children's and adolescents' physical activity, sedentary behavior, and weight status after adjusting for child age, sex, race/ethnicity, household income, and number of children in the home.
  
  
  RESULTS
  Most scales had acceptable test-retest reliability (intraclass correlations were .54 - .92). Parent and adolescent reports were correlated. Electronic equipment in adolescents' bedrooms was positively related to sedentary behavior. Activity equipment in the home was inversely associated with television time in adolescents and children, and positively correlated with adolescents' physical activity. Children's BMI z-score was positively associated with having a television in their bedroom.
  
  
  CONCLUSIONS
  The measures of home electronic equipment and activity equipment were similarly reliable when reported by parents and by adolescents. Home environment attributes were related to multiple obesity-related behaviors and to child weight status, supporting the construct validity of these scales.
authors.affiliation: Joint Doctoral Program in Clinical Psychology, San Diego State University and the University of California, San Diego, CA, USA. drosenberg@ucsd.edu.
authors.forename: Dori E
authors.initials: DE
authors.lastname: Rosenberg
authors.forename: James F
authors.initials: JF
authors.lastname: Sallis
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Kerr
authors.forename: Jason
authors.initials: J
authors.lastname: Maher
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Norman
authors.forename: Nefertiti
authors.initials: N
authors.lastname: Durant
authors.forename: Sion K
authors.initials: SK
authors.lastname: Harris
authors.forename: Brian E
authors.initials: BE
authors.lastname: Saelens