Introduction. A total of 1,061 patients presenting with emotional disorder symptoms (anxiety, depression, and somatization) were enrolled in the PsicAP trial, a randomized, single-blind, two-arm clinical trial conducted across 22 primary care centers in Spain. Of these, 631 participants (TAU = 316; TD-CBT + TAU = 315) completed the full intervention and all pre- and post-treatment assessments; 511 participants (TAU = 238; TD-CBT + TAU = 273) completed baseline and 3-month follow-up assessments; and 388 participants (TAU = 180; TD-CBT + TAU = 208) also completed the 12-month follow-up. The assessment battery included measures of symptoms, emotion regulation strategies (ERS), and quality of life (QoL).
Purpose. The present study examines the potential mediating effect of several ERS—adaptive (reappraisal) and maladaptive (suppression, metacognition, rumination, and worry)—in the relationship between treatment group assignment and the four QoL domains (physical, psychological, social, and environmental) at short- and long-term follow-up.
Method. Multivariate mediation analyses will be conducted using the PROCESS macro for SPSS (Hayes, 2017), with 10,000 bootstrap resamples. Treatment group assignment (TAU vs. TAU + TD-CBT) will be entered as the independent variable, ERS as mediators, and QoL domains at 3 and 12 months as dependent variables.
Results. The findings will address the role of ERS as potential mechanisms of change underlying the transdiagnostic treatment in primary care, particularly in enhancing QoL in the TD-CBT + TAU condition, as well as the variance across QoL domains.
Conclusions. These results will contribute to a better understanding of the mechanisms of change driving the efficacy of TD-CBT, with a specific focus on the mediating role of ERS in improving quality of life.