["Criminal Behaviour and Mental Health, Volume 31, Issue 2, Page 109-119, April 2021. ", "\nAbstract\n\nBackground\nEvidence‐based treatments in routine clinical practice often fail to achieve or sustain amelioration of severe behaviour problems in adolescents. Better understanding of mechanisms underlying such severe behaviour problems could improve treatments. Underlying schemata and schema modes may play an important role.\n\n\nAims\nTo compare early maladaptive schemata, schema modes and behaviour problems in adolescent boys showing disruptive and offending behaviours with those in typically developing boys. We hypothesised a relationship between disconnection and rejection schemata on the one hand and behaviour problems (including offending) on the other in adolescent boys with disruptive behaviour disorders. We also hypothesised that this offending group would differ significantly from typically developing boys on these measures and that schema modes would mediate relationships between schemata and overt behaviours.\n\n\nMethod\nIn this cross‐sectional study, fifty‐five 12–19‐year‐old boys with disruptive behaviour disorders referred to an in‐ or out‐patient clinic were matched to fifty‐five typically developing boys from a previously generated school sample. Group differences on self‐reported schema related measures and externalising behaviour measures were compared using t‐tests. Mediation analyses were performed to assess the mediating role of schema modes in the relation between schemata and behaviour.\n\n\nResults\nBoys diagnosed with disruptive behaviour disorders and engaging in offending behaviours had higher scores on externalising modes and lower scores on healthy modes than the typically developing boys. There were no differences between these groups, however, in disconnection and rejection schemata. In the offending behaviour group, externalising modes mediated the relationship between disconnection and rejection schemata and externalising behaviours while healthy modes mediated a relationship between these schemata and overt prosocial behaviours.\n\n\nImplications\nThe potential impact of healthy modes has not previously been shown in studies of schemata in young offenders. Our findings suggest that treatments for adolescents with severe behaviour problems should not only target maladaptive schemata and dysfunctional modes, but seek also to boost healthy modes.\n\n"]