The prevalence and impact of large sudden improvements during adolescent therapy for depression: a comparison across cognitive-behavioral, family, and supportive therapy.

This study assessed the treatment specificity and impact on outcome of large, abrupt symptomatic improvements occurring prior to and during cognitive-behavioral, family, and supportive therapy. Eighty-seven depressed adolescents receiving at least 8 therapy sessions were included. Abrupt large decreases in depressive symptoms were identified by changes in weekly Beck Depression Inventory scores. Overall, 28% experienced a pretreatment gain and 39% a sudden within-treatment gain. Both types of gains were associated with superior outcome on self-report and interviewer ratings of depression. Among those participants failing to experience a pretreatment or sudden within-treatment gain, cognitive-behavioral therapy produced the superior outcomes. These findings suggest pretreatment and sudden within-treatment gains are important therapeutic events worthy of further investigation.