My theory is that "impostor syndrome" is just another facet/manifestation of anxiety.
While many people do have anxiety time to time, for some the degree is high, and it manifests as the impostor syndrome. (worrying if they are good enough, or over anxious about the tasks not being done correctly, feeling not being a good performer, etc, when they are actually performing great).
I'd say, the same CBT techniques that help people deal with anxiety will help with the 'impostor syndrome' as well. (things like gradual exposure, getting used to the new situation, stepping back and accurately assessing the situation (like a third person) etc).
While many people do have anxiety time to time, for some the degree is high, and it manifests as the impostor syndrome. (worrying if they are good enough, or over anxious about the tasks not being done correctly, feeling not being a good performer, etc, when they are actually performing great).
I'd say, the same CBT techniques that help people deal with anxiety will help with the 'impostor syndrome' as well. (things like gradual exposure, getting used to the new situation, stepping back and accurately assessing the situation (like a third person) etc).