Anxiety disorders are the most prevalent psychiatric disorders, occurring in among 15% to 20% of children. Cognitive behavioral therapy (CBT) is currently the first-choice treatment for anxiety-disordered children. Despite proven efficacy, almost half of them do not respond, causing prolonged suffering. Children with persistent anxiety have an increased risk for other psychiatric disorders, school dropout, social isolation, alcoholism, and suicide attempts. Another concern is that only a small proportion of anxiety-disordered children actually receive treatment. These negative consequences in combination with the limited accessibility of treatment endorse the urgent need to develop more effective and accessible treatments that can enhance effectiveness of current treatment options.

A newly emerging and promising childhood anxiety treatment is Attention Bias Modification Treatment (ABMT). ABMT is build upon evidence that anxious children tend to selectively focus their attention on threatening information in the context of other non-threatening information, and that attention bias is related to development and maintenance of anxiety disorders. Children with an attention bias scan their environment for potential threat or danger thereby starting a cascade of subsequent processing biases in interpretation and memory, resulting in heightened anxiety.

Hence, as attention bias is an underlying mechanism of anxiety, treatment that diminishes attention bias toward threat in anxiety-disordered individuals should alleviate anxiety. Subsequently, several researchers began to examine the effect of ABMT, which implicitly trains anxiety-disordered individuals to attend away from threat toward neutral information. This is a different approach than CBT, which does not target early and automatic information processes, but addresses later stages of information processing that are under volitional control. Several studies highlighted the potential of ABMT in reducing anxiety levels in adults. A meta-analysis revealed that ABMT in adults produces significantly greater reductions in anxiety than sham control training, with a large effect size in clinical populations. A previous study found that 72% of the adults were free from their primary anxiety disorder after ABMT as compared to 11% after sham attention training, which is far more than CBT. These training effects were maintained at 4-month follow-up. Importantly, ABMT also modifies neural systems that are involved in the control of attention to emotional stimuli, in particular the lateral prefrontal cortex.

Despite the promising results in adults, ABMT has been scarcely examined in children. A few studies demonstrated a significant anxiolytic effect of ABMT, but not of the sham control condition. A major limitation of previous studies is that sample sizes were quite low and that a limited number of training sessions were provided. It has been shown that more training sessions enhance the magnitude of treatment effect. This is the first study that examines the effectiveness of a 9-session web-based ABMT in a large sample of anxiety-disordered children as well as examines the additive effect of web-based ABMT on CBT.

As reviewed above, childhood anxiety disorders are highly prevalent and debilitating, and there is an urgent need for improvement of current treatment strategies. An innovative, but scarcely examined, treatment option for childhood anxiety disorders is ABMT. A randomized, sham-controlled, double-blind trial of web-based Attention Bias Modification Treatment for childhood anxiety disorders will be conducted. One hundred twenty-eight children will be randomly allocated to a 9 session internet-delivered ABMT or sham attention training. The primary aim is to compare ABMT-augmented CBT with CBT as monotherapy on recovery rates for anxiety disorders and changes in anxiety. The secondary aim is to compare ABMT with sham attention training on anxiety disorder recovery rates and changes in anxiety.