Effectiveness of YouRAction, an Intervention to Promote Adolescent Physical Activity Using Personal and Environmental Feedback: A Cluster RCT

Background: In this study the one and six months effects of the computer-tailored YouRAction (targeting individual level determinants) and YouRAction+e (targeting in addition perceived environmental determinants) on compliance with the moderate-to-vigorous physical activity (MVPA) guideline and weight status are examined. In addition the use and appreciation of both interventions are studied. Methods: A three-armed cluster randomized trial was conducted in 2009-2010 with measurements at baseline, one and six months post intervention. School classes were assigned to one of the study arms (YouRaction, YouRAction+e and Generic Information (GI) control group). MVPA was derived from self-reports at baseline, one and six months post intervention. Body Mass Index and waist circumference were measured at baseline and six months post intervention in a random sub-sample of the population. Use of the interventions was measured by webserver logs and appreciation by self-reports. Multilevel regression analyses were conducted to study the effects of the intervention against the GI control group. ANOVA's and chi-square tests were used to describe differences in use and appreciation between study arms. Results: There were no statistically significant intervention effects on compliance with the MVPA guideline, overweight or WC. Access to the full intervention was significantly lower for YouRAction (24.0%) and YouRAction+e (21.7%) compared to the GI (54.4%). Conclusion: This study could not demonstrate that the YouRAction and YouRAction+e interventions were effective in promoting MVPA or improve anthropometric outcomes among adolescents, compared to generic information. Insufficient use and exposure to the intervention content may be an explanation for the lack of effects

Self-reported and objectively measured exposure to intervention content by intervention group and differences between intervention groups.

<p>GI = general information; SD = standard deviation; N = number of adolescents; k = number of classes;</p>†<p>based on one-way ANOVA;</p>‡<p>based on chi-square tests.</p

Appreciation of YouRAction, YouRAction+e and GI reported by adolescents who at least used the intervention once and differences between intervention groups.

<p>GI = general information; SD = standard deviation; N = number of adolescents; k = number of classes;</p>†<p>5 point scale (1–5);</p>‡<p>based on one-way ANOVA;</p>§<p>based on chi-square tests.</p

Baseline and six month post intervention compliance with the MVPA guideline and unstandardized regression coefficients of the effects of YouRAction vs GI stratified for adolescents with a Western or non-Western ethnic background.

<p>GI = general information; CI = confidence intervals; N = number of adolescents; k = number of classes;</p>†<p>multilevel linear or logistic regression analyses with class and individual as levels, adjusted for level of education;</p><p>* = p<0.05.</p

Flow diagram of the selection and enrolment of the study participants.

<p>Flow diagram of the selection and enrolment of the study participants.</p

Baseline class and adolescent characteristics of adolescents in complete case analyses for the YouRAction, YouRAction+e, GI and total group.

<p>SD = standard deviation; GI = general information;</p><p>* = p<0.05; derived from multinomial regression analyses.</p