A Randomized Controlled Effectiveness Trial of Acceptance and Commitment Therapy and Cognitive Therapy for Anxiety and Depression

Acceptance and commitment therapy (ACT) has a small but growing database of support. One hundred and one heterogeneous outpatients reporting moderate to severe levels of anxiety or depression were randomly assigned to traditional cognitive therapy (CT) or to ACT. To maximize external validity, the authors utilized very minimal exclusion criteria. Participants receiving CT and ACT evidenced large, equivalent improvements in depression, anxiety, functioning difficulties, quality of life, life satisfaction, and clinician-rated functioning. Whereas improvements were equivalent across the two groups, the mechanisms of action appeared to differ. Changes in "observing" and "describing" one's experiences appeared to…