Efficacy of a Web-Enabled, School-Based, Preventative Intervention to Reduce Bullying and Improve Mental Health in Children and Adolescents: Study Protocol for a Cluster Randomized Controlled Trial - Diaz-Caneja, Covadonga M; Martin-Babarro, Javier; Abregu-Crespo, Renzo; Huete-Diego, Miguel A; Gimenez-Dasi, Marta; Serrano-Marugan, Isabel; Arango, Celso (Frontiers in Pediatrics, 2021)