Anxiety disorders include disorders that share features of excessive fear and anxiety and related behavioural disturbances (APA, 2013). Anxiety disorders differ from developmentally normative fear or anxiety by being excessive or persisting beyond developmentally appropriate periods and this category of disorders includes specific phobias, panic disorder, social anxiety disorder and generalised anxiety disorder. The World Health Organisation estimates that there are 264 million people living with anxiety and diagnoses of anxiety disorders are more common among women than men (4.6% compared to 2.6% at the global level) (World Health Organization, 2017).