Intervention and Mediation Effects of Target Processes in a Randomized Controlled Trial of Acceptance and Commitment Therapy for Anxious Cancer Survivors in Community Oncology Clinics

Abstract

Objective: Acceptance and Commitment Therapy (ACT) is a promising intervention for cancer survivors, but its mechanisms in real-world settings are not fully understood. This study examined ACT-specific and broader target processes as mediators in the Valued Living randomized controlled trial, which compared ACT and usual care for anxious cancer survivors in a real-world community oncology setting.Method: Two ACT-specific target processes (experiential avoidance and values-aligned behavior, each measured with two validated instruments) and two broader target processes (emotional approach coping and self-compassion) were analyzed at Pre- and Post-intervention as predictors and mediators of anxiety symptoms, cancer-related trauma symptoms, and fear of cancer recurrence in a causal steps framework (n = 117). Results: During the intervention, ACT participants improved significantly more than usual care participants on the broader target processes (ps <= .035) but not the ACT-specific target processes (ps >= .080). Cancer-related emotional approach coping mediated cancer-related trauma symptoms and fear of recurrence (ps .043-.044). Self-compassion mediated fear of recurrence (p = .045), and showed marginal patterns for trauma symptoms (p = .059) and anxiety symptoms (p = .084).Conclusion: ACT may work in real-world settings for cancer survivors by promoting self-compassion and coping through emotional processing and expression.

Examining the Effects of Prior Acceptance and Commitment Therapy (ACT) Treatment Among Anxious Cancer Survivors During the COVID-19 Pandemic: Evidence from a Randomized Controlled Trial

“…Higher scores on this measure indicate greater EAC use. Improvement in EAC marginally or significantly mediated intervention effects in the Valued Living RCT, indicating that it is mechanistically linked to anxiety maintenance in the present sample (Fishbein et al, 2021).…”

“…If the intervention had been longer, more individually tailored, or had focused on coping with novel stressors, its effect during the COVID-19 pandemic might have been greater. Finally, ACT participants declined more on emotional approach coping, a variable that was shown to mediate treatment effects in the full trial sample (Fishbein et al, 2021), raising a potential mechanistic explanation for the worsening on the other outcomes observed in the ACT study.…”

Network intervention analysis of anxiety-related outcomes and processes of acceptance and commitment therapy (ACT) for anxious cancer survivors

“…Lower scores on these measures indicate lower anxiety/fear. In the Valued Living trial, the ACT condition showed greater improvement from Pre to Post (Fishbein et al, 2022) and from Pre to FU (Arch et al, 2021) on trauma symptoms and fear of recurrence. However, the conditions did not differ in change on HADS-A anxiety symptoms from Pre-to Post-intervention, and the ACT condition showed only marginally greater improvement than MEUC on anxiety symptoms from Pre-intervention to the 8-month follow-up timepoint.…”

“…Information regarding the full set of variables assessed in the Valued Living trial is provided by colleagues (2019, 2021). By design, the current study parallels the standard mediation analysis of the Valued Living trial (Fishbein et al, 2022) in that it examines three putative processes of the ACT intervention and three anxiety-related outcomes that were administered at each trial timepoint. Each variable's conditional means by timepoint are provided in Supplemental Figure A1 (see Appendix A).…”

“…The main purpose of the present study was to compare network analysis results to the known findings of the standard mediation analysis (Fishbein et al, 2022), and specifically, to examine whether those analytic approaches indicated the same pattern of relationships among intervention processes and outcomes. The current exploratory analysis thus investigated whether the same indirect intervention effects of self-compassion and EAC on anxiety-related outcomes observed in the standard mediation analysis would emerge in the pre-to post-treatment network.…”