It's a shame that the imagining is so expensive, because I'd love to see a true control arm with placebos and follow up scans.
i.e. if you are on a placebo and are told you will get better how many do?
i.e. if you are on a placebo and are told you will get better how many do?
Secondly the 'covert treatment' aspect, and as far as I know only Hjorth et al. do in any reasonable numbers is the giving someone the treatment and usual and tell them it's a placebo and they "shouldn't expect to get better".
It's ethically tricky to do that with an anxiety disorder but I imagine a doctor telling someone with depression that will be painfully close to "you're not getting better", "we're not going to help you" and other quite rejecting disheartening ideas.
But plain placebo controlled SSRI trials I think show about a 0.2 absolute benefit in SSRIs in depression. i.e. if you compare SSRI with placebo you need to treat 5 people with SSRI to see one more person respond. If you compare SSRI with no treatment, you only need to treat 3 people with depression, to have 1 more respond. Those 3 and 5 are called the 'number needed to treat' and can be compared to the 'number needed to harm'.