Mediators of treatment effect in minimal-contact cognitive behaviour therapy for severe health anxiety: A theory-driven analysis based on a randomised controlled trial

Brief scales for the measurement of target variables and processes of change in cognitive behaviour therapy for major depression, panic disorder and social anxiety disorder

BACKGROUND

The measurement of process variables derived from cognitive behavioural theory can aid treatment development and support the clinician in following treatment progress. Self-report process measures are ideally brief, which reduces the burden on patients and facilitates the implementation of repeated measurements.

AIMS

To develop 13 brief versions (3-6 items) of existing cognitive behavioural process scales for three common mental disorders: major depression, panic disorder, and social anxiety disorder.

METHOD

Using data from a real-world teaching clinic offering internet-delivered cognitive behavior therapy (n=370), we drafted brief process scales and then validated these scales in later cohorts (n=293).

RESULTS

In the validation data, change in the brief process scales significantly mediated change in the corresponding domain outcomes, with standardized coefficient point estimates in the range of -0.53 to -0.21. Correlations with the original process scales were substantial (r=.83-.96), internal consistency was mostly adequate (α=0.65-0.86), and change scores were moderate to large (|d|=0.51-1.18). For depression, the brief Behavioral Activation for Depression Scale-Activation subscale was especially promising. For panic disorder, the brief Agoraphobic Cognitions Questionnaire-Physical Consequences subscale was especially promising. For social anxiety disorder, the Social Cognitions Questionnaire, the Social Probability and Cost Questionnaire, and the Social Behavior Questionnaire-Avoidance and Impression Management subscales were all promising.

CONCLUSIONS

Several brief process scales showed promise as measures of treatment processes in cognitive behaviour therapy. There is a need for replication and further evaluation using experimental designs, in other clinical settings, and preferably in larger samples.

Mediators during a Multimodal intervention for stress-induced exhaustion disorder

Our understanding of the underlying psychological processes of development, maintenance, and treatments for stress-induced exhaustion disorder (ED) remains limited. Therefore, the current study aimed to explore whether sleep concerns, pathological worry, perfectionistic concerns, and psychological flexibility mediate change in exhaustion symptoms during a Multimodal intervention for ED based on Cognitive behavioral therapy principles. Participants (N = 913) were assessed at three time points, and mediation was explored using a two-criteria analytical model with linear mixed-effects models (criterion one) and random intercepts cross-lagged panel modeling (criterion 2). Criterion one for mediation was successfully met, as the findings indicated significant associations between time in treatment, with all suggested mediators, and exhaustion symptoms (significant ab-products). However, criterion two was not satisfied as changes in the mediators did not precede changes in exhaustion symptoms. Therefore, mediation could not be established. Instead, changes in the suggested mediators appeared to result from changes in exhaustion symptoms. Consequently, sleep concerns, pathological worry, perfectionistic concerns, and psychological flexibility appear to improve in conjunction with exhaustion symptoms during treatment, where improvement in exhaustion is indicated as the main driving factor, based on this exploratory analysis. The implications of these findings are contextualized within a broader framework of process-based therapy.

Therapeutic processes in digital interventions for anxiety: A systematic review and meta-analytic structural equation modeling of randomized controlled trials

While the efficacy of Internet- and mobile-based interventions (IMIs) for treating anxiety disorders is well established, there is no comprehensive overview about the underlying therapeutic processes so far. Thus, this systematic review and meta-analysis evaluated research on mediators and mechanisms of change in IMIs for adult anxiety disorders (PROSPERO: CRD42020185545). A systematic literature search was performed in five databases (i.e., CENTRAL, Embase, MEDLINE, PsycINFO and ClinicalTrials.gov). Two reviewers independently screened studies for inclusion, assessed the risk of bias and adherence to quality criteria for process research. Overall, 26 studies (N = 6042) investigating 64 mediators were included. Samples consisted predominantly of participants with clinically relevant symptoms of generalized anxiety disorder and severe health anxiety, as well as of participants with non-clinically relevant anxiety symptoms. The largest group of examined mediators (45%) were cognitive variables, evincing also the second highest proportion of significance (19/29); followed in numbers by skills (examined: 22%; significant: 10/14) and a wide range of other (19%; 7/12), emotional/affective (11%; 2/7) and behavioral mediators (3%; 1/2). Meta-analytical synthesis of mediators, limited by a small number of eligible studies, was conducted by deploying a two-stage structural equation modeling approach, resulting in a significant indirect effect for negative thinking (k = 3 studies) and non-significant indirect effects for combined cognitive variables, both in clinical (k = 5) and non-clinical samples (k = 3). The findings of this review might further the understanding on presumed change mechanisms in IMIs for anxiety, informing intervention development and the concurrent optimization of outcomes. Furthermore, by reviewing eligible mediation studies, we discuss methodological implications and recommendations for future process research, striving for causally robust findings. Future studies should investigate a broader range of variables as potential mediators, as well as to develop and apply original (digital) process and engagement measures to gather qualitative and high-resolution data on therapeutic processes.