An attention bias modification training as waitlist intervention for depression:
A randomized controlled trial

Usual care for Major Depressive Disorder (MDD) consists of a mix of
interventions, most of them evidence-based like psychotherapy and
antidepressants. However, these interventions are costly and response and
remission rates are rather low. Moreover, once referred to specialty care,
patients often have to wait months until they actually do receive treatment.
Hence, cost-effective and easily accessible treatment options that could be
offered during waiting period are urgently needed. A recently developed,
computerized training method, the so-called cognitive bias modification (CBM)
may have the potential to be provided as cost-effective waitlist intervention
for MDD. CBM aims at targeting the cognitive biases often found in depression.
Due to these biases, patients suffering from this disorder, preferentially
attend to negative information, or interpret and remember ambiguous situations
in a more negative manner than healthy individuals do. However, depressed
patients also lack positive biases (i.e., a heightened processing of positive
information) usually found in healthy individuals. A growing body of literature
suggests, that these biases play an important role in the development and
maintenance of the disorder. One form of CBM, the so-called attention bias
modification (ABM) trains participants to allocate their attention away from
negative and towards neutral or positive information and thus aims at
decreasing a negative and at increasing a positive attentional bias
respectively. Studies on the effectiveness of ABM in depressed samples are
scarce, but provide preliminary evidence that ABM can modify attentional
processes in depression and may be of therapeutic value for this group.
However, so far, no ABM study has been conducted in patients with a major
depression yet, using the most promising training procedure, that is the
dot-probe task, and no clinical studies are available using ABM as waitlist
intervention for depression.

Aim of the study is to evaluate the effectiveness and cost-effectiveness of a
positivity training based on attention bias modification as
waitlist-intervention for adult outpatients with a major depressive disorder.

A double blind randomized controlled trial in two groups with a 1, 6 and 12
months follow-up combined with an economic evaluation.

A computerized positivity training, based on cognitive bias modification (CBM)
for attention, is offered eight times during a period of two weeks (i.e., 4
weekly sessions), for 25 minutes per session. Besides the first, all training
sessions are completed via the internet, at participant*s home. In the
positivity training patients learn to attend to positive information and to
avoid negative information. In the control condition, patients receive a
sham-training, during which attentional bias is continuously assessed but not
modified.

ABM is a non-invasive, safe procedure that it is very unlikely to produce any
side effects and requires a minimum of time and effort from patients. Patients
have to visit the lab only three times in total, as seven of the training
sessions and all follow-up measures are completed via the internet at home and
need no site visit. As recent research has shown, that even CBM sham training
groups improve with regard to symptom severity from before to after the
training (Enock & McNally, 2013; McNally, Enock, Tsai, & Tousian, 2013), which
might be for instance due to a placebo effect or maybe even due to an increase
in attentional control, both groups of participants can be expected to benefit
to some extend from the training. However, only the positivity training is
expected to induce a positive attentional bias and in turn should be more
effective in reducing depressive symptoms than the sham training. Moreover, all
participants receive standard care (i.e., cognitive behavioral therapy)
delivered in the programme for mood disorders of Pro Persona.