Discussion
anxiety, NSSI, assessor-rated, psychiatric, depression
Findings of this randomized clinical trial support the efficacy of this IERITA delivered adjunctive to TAU (vs TAU only). IERITA resulted in greater improvements in NSSI frequency (both self-reported and assessor-rated) and emotion dysregulation from pretreatment to 1-month posttreatment than TAU only. Results also revealed superior effects of IERITA plus TAU (vs TAU only) on global functioning and other self-destructive behaviors, with between-group effect sizes in the moderate range. Notably, treatment effects were maintained at 3-month posttreatment, suggesting durability of effects. Finally, week-to-week improvements in emotion dysregulation mediated week-to-week reductions in NSSI frequency in IERITA, providing further support for the theoretical framework underlying this treatment.The conditions did not differ significantly in psychiatric symptoms at 1 or 3 months following treatment, suggesting that IERITA results in improvements in emotion dysregulation and global functioning despite comparable levels of depression and anxiety (relative to TAU). These findings are consistent with the emphasis in IERITA on the acceptance of internal experiences and control of behaviors in the context of emotional distress (vs the control or downregulation of emotions themselves), and suggest that targeting emotion regulation may not be sufficient for the treatment of anxiety and depression among adolescents.