Influence of family therapy on bullying behaviour, cortisol secretion, anger, and quality of life in bullying male adolescents: A randomized, prospective, controlled study.

OBJECTIVE: To determine the influence of brief strategic family therapy (BSFT) on salivary cortisol, anger, and health-related quality of life (QoL) in adolescent boys with bullying behaviour. METHOD: We selected a sample of 72 boys demonstrating bullying behaviour from the general population and treated 36 with BSFT for 12 weeks. The other 36 boys formed the control group. Primary outcome measures were salivary cortisol concentration 15 to 30 minutes after awakening and changes on the subscales of the State-Trait Anger Expression Inventory (STAXI) and the Health Survey (SF-36). RESULTS: After 12 weeks' treatment, we observed a significant reduction in bullying behaviour in the BSFT group (P = 0.017) and in the mean values (according to the intent-to-treat principle) for salivary cortisol concentration (P < 0.001). The BSFT group also showed significantly greater change on the STAXI subscales State-Anger (P < 0.001), Trait-Anger (P < 0.001), Anger-Out (P < 0.001), and Anger-Control (P < 0.001). Treatment with BSFT also resulted in significant improvement on the SF-36 subscales for Vitality (P < 0.001), Social Functioning (P < 0.001), Role-Emotional (P < 0.001), and Mental Health (P < 0.001). CONCLUSIONS: BSFT effectively influenced bullying behaviour, salivary cortisol concentration, anger, and health-related QoL in adolescent bullying boys.