Esther Mertens

64 | Chapter 3 It appears that using a psychophysical approach is a method that fits well with interventions targeting prevocational students; the alternation between psychological instruction or reflection and physical exercises or games possibly increase students’ engagement in the intervention (Ter Vrugte et al., 2015), enabling them to optimally benefit from the intervention. Most intervention effects were found in students’ intrapersonal domain. Only one intervention effect (aggression, and two trends for interpersonal relations in the class and bullying) was found in the interpersonal domain. A possible explanation for the larger impact of R&W in the intrapersonal domain could be that a more physical approach is used when addressing that domain, while a more verbal approach is used when focusing on the interpersonal domain. Based on the description in the intervention’s manual (Ykema 2002; 2018), the main emphasis in the exercises and games is on students’ own feelings, emotions, and attitudes (i.e., the intrapersonal domain). “Was your breathing low? Were you balanced and calm during the game?” Students’ attitudes and behaviors in relation to others (i.e., the interpersonal domain) is mainly addressed during (verbal) role-play and discussions when sharing thoughts together. They discuss, for instance, what bullying is and what students can do about it. “How did the bully feel when they said ‘stop’ together?” This more verbal approach is cognitively more demanding and could possibly hinder prevocational students to benefit from the intervention in the interpersonal domain. Regarding the secondary outcomes, positive intervention effects were found for three of the four underlying competencies that are important according to the theory of R&W (i.e., self-control, emotional self-regulation, and a trend regarding self-esteem) indicating the intervention’s potential. However, no intervention effect was found in students’ self-reflection which is one of the pillars of the R&W house. Also previous interventions appeared to be ineffective in improving self-reflection of prevocational students. For instance, Ter Vrugte and colleagues (2015) examined the effectiveness of a game to improve math skills in prevocational students. This game included a reflection stimulating component, but they found no effect on students’ reflection. Perhaps, self- reflection is cognitively too demanding and abstract for prevocational students since it requires thinking on the metacognition level (Sauter et al., 2010). Nonetheless, as self- reflection has been indicated as a potential effective component in universal school- based interventions (Mertens et al., 2020), future research should examine whether self-reflection is an effective intervention component for prevocational students and, if so, how self-reflection can be stimulated in these students. The intervention effects were strongest during the first part of the intervention and leveled off to insignificant effects in the second year, indicating that it might be sufficient to only implement the first year of the intervention. A decline in intervention effects in relatively long interventions has been found previously in meta-analyses examining different types of interventions (Bakermans-Kranenburg, Van IJzendoorn, & Juffer, 2003; Cuijpers, 2000; De Mooij, Fekkes, Scholte, & Overbeek, 2019). These meta- analyses suggest that short-term interventions with a modest number of sessions are