John: Hello, I'm John Hilton, senior editor at Cochrane. The Cochrane Common Mental Disorders Group has produced many reviews of the effects on interventions for conditions such as anxiety and depression. They added to these in November 2020 with a substantially revised version of their review of the use of cognitive behavioural therapy for children and adolescents. We asked one of the authors, Tessa Reardon from the University of Oxford in the UK, to tell us about the importance of this review and what it found.

Tessa: Anxiety disorders are the most common mental health disorders experienced by children and adolescents. They have a negative impact on the children and their family's day-to-day lives, and, as the children move into adulthood, these disorders put them at risk for ongoing anxiety, other mental health problems and reduced quality of life. It's therefore really important that we ensure that children with anxiety disorders have access to treatments that are known to be effective.
Cognitive Behavioural Therapy, which is commonly called CBT, is a type of psychological treatment that typically involves helping the person to identify and modify anxious thoughts and feelings, and gradually face their fears. Previous Cochrane Reviews in 2005 and 2015 found that CBT is an effective treatment for anxiety disorders in children and adolescents but we know that families often struggle to access treatment and support for anxiety difficulties in children, and very few access services that offer CBT. Therefore, one way to help ensure children can access effective anxiety treatments, is to clearly show the effectiveness of these treatments and to deliver them in as efficient a way as possible.
Our review should help with this by presenting up-to-date evidence on CBT for anxiety disorders in children and adolescents under 19 years of age. We wanted to find out if CBT is more effective at treating childhood anxiety disorders than no, or another treatment, or putting the child on a waiting list for CBT.  We looked at a range of outcomes, both immediately after treatment and in the longer term. We also investigated whether there were any differences in outcomes with different types of CBT, such as one-to-one versus group; therapists working with the child only, the child and parent together or the parent only; or shorter versus longer treatments; or among specific groups such as children with autism or different age groups.
We are now able to include 87 studies, involving almost 6000 children with anxiety disorders in the analysis, which is more than twice as many studies as the previous Cochrane review. This evidence shows that CBT is more effective in the short-term than no treatment or a waiting list, with benefits across anxiety and broader outcomes. However, there is still no evidence that one way of providing CBT, for example in groups or for longer periods, is more effective than any other, or that CBT works better or worse for any specific group of children.  Few studies include longer-term follow-up, so we also cannot be sure whether benefits continue in the medium to long term.  We also didn't find evidence that CBT is more effective than other types of treatments, but we are not so sure about this because few studies compared CBT to alternative treatments.
In conclusion, we now have sufficient evidence that CBT is an effective treatment for anxiety disorders in children and adolescents. Encouragingly, our findings indicate that relatively brief CBT treatments can be delivered without a negative impact on short-term outcomes.  However, not all children and adolescents with anxiety disorders benefit from CBT and many who may benefit still don't access it. Therefore, important steps remain, including finding out how best to improve outcomes for all children and young people with anxiety disorders and ensuring that effective treatment is available for those who may benefit.

John: If you would like to look into the review's findings in more detail, it's available online, at the Cochrane Library dot com. A simple search of the website for 'CBT for anxiety in children' will find it for you.