The Working Mechanisms behind the Effectiveness of ‘Happy at School'. Processes of Mediation in a Preventive Training Program

Introduction: Studying the effectiveness of intervention programs has become a well-established research procedure. However, less is known about the working mechanisms of interventions. ‘Happy at School’ is an indicated preventive social skills training program for children that are about to make the transition to secondary school. The program is found to be effective in preventing and reducing internalizing problems and peer problems in secondary school. ‘Happy at School’ is based on cognitive behavioral therapy. The purpose of this study is to examine the working mechanisms of ‘Happy at School’ by studying mediation of the effect through positive and negative thoughts on the outcome measures social anxiety, self-esteem, victimization and social disintegration. 

 

Methods: A total of 374 children participated in a cluster randomized controlled trial (184 in the intervention group, Mage = 12 years, SD = 6.14 months, 43% boys). Independent variable was the treatment condition. Dependent variables were social anxiety, self-esteem, victimization and social disintegration at two follow-up measurement waves (7 and 41 weeks post-intervention; T2 & 3). Mediators were positive and negative thoughts at posttest and first follow-up measurement (2 and 7 weeks post-intervention; T1 & 2). Control variables were baseline (pre-intervention; T0) dependent variables and gender. The mediational model was tested using Structural Equation Modeling.

Results: Negative thoughts  at T1 mediated the relation between treatment condition and both the dependent variables social anxiety at T2 (after xx months) (B = -.02, p < .05) and self- esteem at T2 (B = .05, p < .05). Children in the intervention group had less negative thoughts (social anxiety model: B = -.12, p < .05, self-esteem model: B = -.11, p < .05 ), which leads to less social anxiety (B = .02, p < .001) and to higher self-esteem (B = -.43, p < .001).

Positive thoughts at T1 mediated the relation between treatment condition and both the dependent variables social anxiety T2 (B = -.01, p < .05) and self-esteem T2 (B = .04, p < .05). Children in the intervention group had less negative thoughts (B = -.15, p < .05 in both models), which leads to less social anxiety (B = .08, p < .001) and to higher self-esteem (B = -.31, p < .001).

            Positive and negative thoughts did not mediate the relation between treatment condition and the dependent variables social anxiety and self-esteem at T3 and victimization and social disintegration at T2 and T3.

 

Conclusion: Results showed that decreasing negative thoughts and increasing positive thoughts are working mechanisms of the effectiveness of ‘Happy at School’ on social anxiety and self-esteem (on the short term) but not on victimization and social disintegration. Results of this study can be used to refine existing interventions.