Transdiagnostic Internet-delivered Cognitive Behaviour Therapy Research Articles

Reductions in the internalising construct following internet-delivered treatment for anxiety and depression in primary care

Depressive and anxiety disorders are different manifestations of a latent internalising construct. To date, efficacy studies have tended to focus on disorder-specific outcomes, rather than underlying dimensions. This study examined the effect of a transdiagnostic internet-delivered cognitive behavioural therapy (iCBT) on the internalising construct in a primary care sample. Participants included 635 patients aged 18 years or over who were prescribed a six lesson transdiagnostic iCBT program for anxiety and depression by their primary healthcare professional. All patients completed the Patient Health Questionnaire 9, the Generalised Anxiety Disorder 7-Item Scale, the Mini Social Phobia Inventory and the Panic Disorder Severity Self-Report Scale at baseline. 325 of these patients completed the program and provided data on each of these scales during the final lesson. Reductions in the latent internalising construct were assessed within a longitudinal factor analysis framework that compared internalising factor means before and after treatment. The within group mean reduction in the latent internalising construct was large (ES = 1.23, SE = 0.09; p < 0.001). Due to the lack of a control group, between group reductions in the latent internalising construct could not be investigated. This study demonstrated that there are clinically significant reductions in the latent internalising construct following transdiagnostic iCBT for anxiety and depression.

Reductions in negative repetitive thinking and metacognitive beliefs during transdiagnostic internet cognitive behavioural therapy (iCBT) for mixed anxiety and depression

We explored whether transdiagnostic internet-delivered cognitive behavioural therapy (iCBT) for mixed anxiety and depression effectively reduces repetitive negative thinking (RNT), and whether reductions in RNT and positive metacognitive beliefs mediate symptom improvement during iCBT.Participants with generalized anxiety disorder (GAD), major depressive disorder (MDD), or mixed GAD/MDD diagnoses were randomly allocated to a 6-lesson clinician-guided iCBT anxiety and depression program (n = 46) or wait-list control (WLC, n = 53). Depression (PHQ-9), generalized anxiety (GAD-7), RNT (Repetitive Thinking Questionnaire) and positive beliefs about RNT (Positive Beliefs about Rumination Scale) were assessed at pre-, mid-, and post-treatment or matched time points for WLC. Tests of serial indirect effects explored the potential meditating role of RNT and positive belief reductions on the impact of iCBT on depression and anxiety symptoms post-treatment.Results showed that both RNT frequency and positive beliefs about the value of RNT reduced significantly following iCBT compared to WLC, with gains maintained at 3-month follow-up. Reductions between pre- and mid-treatment in positive beliefs and RNT mediated improvements in depression symptoms post-iCBT, and reductions in positive beliefs mediated improvements in GAD symptoms. These findings indicate that iCBT is an effective treatment for RNT and positive metacognitive beliefs. Future dismantling studies are needed to assess the most effective treatment components.