Help may be a few sessions away : understanding early sudden gains in an acceptance and values-based intervention for depression: occurrence, effect and association with competence

Abstract

The aim of this research was to investigate the occurrence and effects of early sudden gains in an acceptance and values-based intervention for depression delivered by novice therapists. The intervention was a semi-structured six-session intervention based on the principles and methods of acceptance and commitment therapy. All participants (n=56) were diagnosed with major depressive disorder by an independent physician. Study I and Study II explored the immediate effect of early sudden gains during the intervention and impact on treatment outcome after the intervention and during the six-month and 12-month follow-up phases. The results suggested that early sudden gains occur relatively frequently in interventions delivered by novice therapists; around 25% of participants were classified as early sudden gainers after two sessions based on the RCI classification (Jacobson & Truax, 1991). Those participants who experienced early sudden gains were also noted for significantly superior treatment outcomes after the six-session intervention both at the levels of depression and psychological flexibility. The large changes associated with early sudden gains were very stable and the treatment effect was maintained up to 12 months after the intervention. Study III sought to explore the possible association between competence and adherence with early sudden gains. All novice therapists (n=37) received a total of four days of training in the methods of acceptance and commitment therapy along with building a case conceptualization. The novice therapists were evaluated by external raters for competence and adherence based on randomly selected video recordings (n=74, two sessions for each therapist) using the ACT Adherence Scale rating system (Plumb & Vilardaga, 2010). Level of competence was linked with the magnitude of early changes in depression. Competence was also associated with overall treatment outcome. These results suggest that early sudden gains are an important and clinically significant phenomenon in the treatment of depression. Given the very limited training of novice therapists, early sudden gains do not appear to require extensive experience from the therapist. At the moment, research literature has yet to identify what explains early sudden gains and more research is necessary to understand possible causal factors.