One hundred sixty parent-adolescent dyads with complete data were included in the analysis (Boston: 32.3%, Cincinnati: 24.9%, San Diego: 42.9%). The adolescent sample was 51.9% female, with a mean age of 14.6 (SD = 1.7) and 41.9% identified themselves as a non Hispanic-white race/ethnicity. The mean age of the parents was 45.1 (SD = 6.8) years and 62% reported a household income greater than or equal to $50k/year.
shows hours/day adolescents spent doing each of the 11 sedentary behaviors during a typical weekday and weekend day as reported by parents and adolescents. Parents and adolescents both reported adolescents spending the most weekday sedentary time doing homework and watching TV/videos/DVDs during the weekend. Both reported that reading a book/magazine not for school was the least common behavior on both weekdays and the weekend (range: .61 – .71 hrs). Test-retest reliability ranged from 0.30 to 0.70 for parent-reported weekday behavior items and 0.29 to 0.85 for weekend behavior items. For adolescent reported sedentary behavior items, reliability ranged from 0.32 to 0.72 and 0.42 to 0.83 for weekday and weekend behavior items, respectively. Lower reliabilities from both parents and children (< .40) were found for more ambiguous items such as “sitting/hanging out/talking with friend” and “doing inactive hobbies”, with higher reliabilities for screen- or device-related behaviors (e.g., TV, calling/texting). Parent-adolescent agreement ranged from 0.32 to 0.63 for weekday activities and 0.29 to 0.66 for weekend sedentary time.
The reliability and agreement for the eight sedentary behavior rules are presented in . The most prevalent rule was “no TV/DVD while doing homework” with 66.2% of parents and 52.8% of adolescents reporting the rule was present. The least commonly endorsed rule (< 5% positive endorsement) was “no TV/computer unless exercised first”. Test-retest reliability coefficients were consistently higher on each item for parents (Kappa range: 0.44 – 0.70) compared to adolescents (Kappa range: 0.43 – 0.61). Agreement between parent and adolescent pairs on the individual rule items tended to be low, with no kappa exceeding 0.53. Composite estimates of parent-adolescent rule agreement were higher with 58.8% on at least five out of the seven rules, 62.5% of dyads having agreement on at least three out of four TV rules and 81.2% agreement on two out of three computer rules.
More than half of adolescents reported the presence of at least one TV in their bedroom (53.8%). Having a video game system or desktop computer in their bedroom was less common (25.8% and 32.3%, respectively). Adolescent report was found to be very similar to parent report for the presence of these items in the bedroom (Kappa > 0.70).
For adolescent report, models explaining TV viewing (R2 = .21, p < .001) and video game use (R2 = .27, p < .001) were significant (). Based on adolescent report, rules for TV, rules for computer use, and total number of screen time rules were significantly negative (more rules, less behavior) correlates of time adolescents spent watching TV (ß = -.22, p < .01), playing video/computer games (ß = −.18, p < .05), and using the internet/computer for entertainment (ß = −.18, p < .05), respectively. Having a TV in the bedroom was related to more TV watching (ß = .24, p < .01). A positive association was found between having at least one video game system in the bedroom with time the adolescent spent playing video games (ß = .19, p < .05). Adolescent age and household income were negatively associated with video game time. Agreement on rules between parents and adolescents and the interaction between agreement and number of rules were not significantly related to any of the three screen time behaviors for the adolescent report models.
Regression models predicting sedentary behaviors – Adolescent report
For parent report, models explaining TV viewing (R2 = .22, p < .001), video game use (R2 = .23, p < .001), and computer use (R2 = .21, p < .001), were significant (). The parent reported models indicated that only rules for TV was associated with less TV viewing time (ß = −.22, p < .05). Similar to adolescent report, parent report of a TV in their adolescents’ bedroom was associated with more adolescent TV watching (ß = .18, p < .05). Agreement on rules between parents and adolescents was significant only for using the internet/computer for entertainment (ß = −.23, p < .01). The rules x agreement interaction was significant for parent report of adolescents’ TV watching time (ß = −.15, p = .10; ) and for video/computer games use (ß = −.16, p < .05; ), but not for computer use.
Regression models predicting sedentary behaviors – Parent report
Model-based estimated interaction of number of rules and rules agreement on TV viewing (a) and video game use (b).
The interaction between rules and availability of media devices in the bedroom was tested but did not reach statistical significance. Further analysis indicated that adolescents reporting the presence of a TV in their bedroom also reported significantly fewer TV rules than those without a TV (F(1,155) = 24.84, p < .001). This finding was replicated with parent reports (F(1,155) = 9.84, p < .001).