Main findings
depression, ABM, anxiety, depressive symptoms
The current study examined the long-term effect of ABM While we did find a general reduction in self-reported depression, anxiety symptoms, and state rumination over the course of this trial, the add-on benefit of this intervention compared to the natural course of symptoms is unknown due to lack of data from the discontinued assessment only group.The intervention failed to modify AB which is the proposed mechanism of ABM. It has been argued that modification of AB is a requirement for ABM to have the intended effect on symptoms (Grafton et al., There is currently no available evidence to support the effectiveness of ABM in long-term reduction of depressive symptoms in adult populations (see also Basanovic et al., After ABM, the development of depressive symptoms up to six months was significantly different among groups. While the change within groups was insignificant, the depressive symptoms among the active condition increased, while it continued to decrease among the sham condition. We speculate that the different trajectories might be related to a withdrawal effect from ABM prior to complete recovery. Pertaining to research on antidepressants, there are some indications for a rebound effect, i.e. higher relapse rates or especially severe relapses of depression after the discontinuation of an antidepressant (Henssler, Heinz, Brandt, & Bschor, This study took place during the covid-19 pandemic and lockdowns, and we do not know how this affected the outcome of this trial. Implicit tuning of AB through ABM may require face-to-face contact to reach its full potential (Godlewska & Harmer, So why did the intervention fail at modifying AB? The intervention has previously been successful in modifying AB (Browning et al., 