FITeens Toolkit

9 time in girls. Larger effect sizes demonstrated by experimental school boys in most of the variables reveal that boys benefited more from the intervention program than girls. This suggests that for optimal effectiveness, school-based health promotion interventions need to be tailored to the population and/or setting involved (Owen et al., 2017). The general consensus is that intervention studies need to conduct long-term follow-ups beyond post-intervention testing to assess maintenance of the intervention effect (Dobbins et al., 2009). An intervention that has been proven to be effective in the long-term has implications for policy decisions, government spending, and ultimately the health of children and adolescents as they progress to adulthood. For instance, a systematic review of follow- up studies revealed that 10 out of 13 school-based physical activity promotion interventions demonstrated sustained impact (Lai et al., 2014). Recently, a different systematic review and meta-analysis was conducted to assess the effectiveness of eHealth (interventions delivered via internet, computers, tablets, mobile technology, or tele-health) school-based multiple health behaviour change interventions to prevent traditional (use of alcohol and tobacco, poor diet, and physical activity) and emerging (sedentary behaviour and sleep) chronic disease risk factors (Champion et al., 2019). Results revealed that eHealth school-based multiple health behaviour change interventions significantly increased fruit and vegetable intake and both accelerometer-measured and self- reported physical activity, and reduced screen time immediately after the intervention. However, no effect on alcohol or tobacco consumption, fat or sugar-sweetened beverage or snack consumption was evident. Moreover, even despite the high proportion of adolescents who own a smartphone (95%) stated by some authors (Vogels, Gelles-Watnick and Massarat, 2022), the potential of mHealth applications to supplement website-based programmes for school students has not been fulfilled. Therefore, future research should explore the feasibility and efficacy of mHealth interventions for lifestyle risk behaviours (Champion et al., 2019).