An examination of sudden gain prevalence across cognitive-behavioural therapy for anxiety and depressive disorders: A quantitative analysis and meta-analytic review.

Sudden gains, incidences of unexpectedly large and stable session to session symptom reductions during psychotherapy, have been shown in samples of individuals receiving treatment for both anxiety and depressive disorders, although seemingly more frequently in sample receiving treatment for depressive disorders. This may suggest that sudden gains are a function of depression, but the high comorbidity between anxiety and depressive disorders makes this difficult to assess. Study One utilised a sample of 117 adults undergoing CBT for a principal anxiety disorder to explore the effect of comorbid depression on sudden gain prevalence.