Evaluation of the Web-Based Computer-Tailored FATaintPHAT Intervention to Promote Energy Balance Among Adolescents Results From a School Cluster Randomized Trial

Objective: To evaluate the short-and long-term results of FATaintPHAT, a Web-based computer-tailored intervention aiming to increase physical activity, decrease sedentary behavior, and promote healthy eating to contribute to the prevention of excessive weight gain among adolescents. Design: Cluster randomized trial with an intervention group and a no-intervention control group. Setting: Twenty schools in the Netherlands. Participants: A total of 883 students (aged 12-13 years). Intervention: The FATaintPHAT (VETisnietVET in Dutch) Web-based computer-tailored intervention. Outcome Measures: Self-reported behaviors (diet, physical activity, sedentary behavior) and pedometer counts were measured at baseline and at 4-month and 2-year follow-up; body mass index (BMI), waist circumference, and fitness were measured at baseline and at 2-year follow-up. Descriptive and multilevel regression analyses were conducted among the total study population and among students not meeting behavioral recommendations at baseline (students at risk). Results: The complete case analyses showed that FATaintPHAT had no effect on BMI and waist circumference. However, the intervention was associated with lower odds (0.54) of drinking more than 400 mL of sugar-sweetened beverages per day and with lower snack intake (beta=-0.81 snacks/d) and higher vegetable intake (beta=19.3 g/d) but also with a lower step count (beta=-10856 steps/wk) at 4-month follow-up. In addition, among students at risk, FATaintPHAT had a positive effect on fruit consumption (beta=0.39 g/d) at 4-month follow-up and on step count (beta=14 228 steps/wk) at 2-year follow-up but an inverse effect on the odds of sports participation (odds ratio, 0.45) at 4-month follow-up. No effects were found for sedentary behavior. Conclusion: The FATaintPHAT intervention was associated with positive short-term effects on diet but with no effects or unfavorable effects on physical activity and sedentary behavior.