Major depressive disorder (MDD) is a prevalent, debilitating and disabling disorder, and its prevalence is increasing. Antidepressants (AD), cognitive-behavioral therapy (CBT) and behavioral activation (BA) are the main treatments for MDD. Trial-based cognitive therapy (TBCT) addresses and restructures dysfunctional negative core beliefs (CBs) and is a novel and promising approach.

The aim of this study was to compare the efficacy of TBCT, BA and treatment as usual (TAU) in the treatment of MDD.

A total of 76 patients with MDD were randomized into 1 of 3 groups and evaluated at baseline, after 6 weeks and at week 12 (final evaluation). The primary outcome was changing in HAM-D scores, and the secondary outcomes included scores on the BDI, CD-Quest, Sheehan Disability Scale (SDS) and WHOQOL.

Both TBCT and BA (which also included AD) were different from TAU (which included antidepressants alone) in reducing the HAM-D and BDI scores and other measures. TBCT and BA were different from TAU in the reduction of disability in SDS and WHOQOL physical domain scores. Besides limited by a small sample size, the dropout rate in the TAU arm was higher, and only 10 patients completed the 3 evaluations.

This trial provides evidence that TBCT and BA combined with antidepressants were more efficacious than the TAU (drug alone) in reducing the severity of depressive symptoms and disability, showing that this combination can be useful for clinical practice.

The best prevention against relapse results when patients are taught to restructure negative core beliefs (CBs). Efficacy of the trial-based thought record (TBTR) in decreasing the credit given by patients to negative CBs and corresponding emotions was evaluated.

Patients (n = 166) were submitted to a simulation of a legal trial to assess their adherence to negative CBs and corresponding emotions after each cognitive therapy technique incorporated by TBTR.

Significant reductions existed in percent values after the first and second defense attorney pleas, as well as after jury's verdict and initial preparation for the appeal (p < 0.001), relative to the investigation phase. Significant differences also emerged between the defense attorney's first and second pleas and between the defense attorney's second plea and jury's verdict, as well as preparation for the appeal (p < 0.001). There was no significant difference between percentages presented by patients submitted to TBTR used in the empty chair format relative to the conventional format. Similarly, there was no difference between outcomes, regardless of therapists’ level of exposure to TBTR.

TBTR may help patients reduce attachment to negative CBs and corresponding emotions. Outcomes were significantly favorable regardless of the format use and therapists’ level of exposure to TBTR.