It's frustrting when you ask someone how they know this works or how effective it is and they give you blank looks. It feels like a failure of informed consent.
> The CBT ppl just blink at me like the question is not on their manual.
What country? In England the IAPT programme (the main source of CBT) has extensive data collection on outcomes (probably the largest collection in the world) and a focus on getting more and better evidence to improve the service.
Chapter 3 and 6 of the IAPT manual are about evidence based practice and gathering better data:
https://www.england.nhs.uk/wp-content/uploads/2018/06/the-ia...
The data sets are here: https://digital.nhs.uk/data-and-information/publications/sta...
The latest (Jun 12 2018) says this
---begin quote---
Key Facts
In April 2018 there were:
-- 119,304 new referrals;
-- 85,145 referrals that entered treatment;
-- 47,296 referrals that finished a course of treatment, of which;
-- 89.4 per cent waited less than 6 weeks and 98.9 per cent waited less than 18 weeks to enter treatment;
-- 44,222 started their treatment at caseness, with 51.9 per cent moving to recovery.
---end quote---
There's some jargon there, but that's explained in the executive summary: https://files.digital.nhs.uk/D3/B3FC5F/iapt-month-apr-2018-e...
tl;dr: CBT is somewhat effective; it's more effective if you have CBT that follows the high intensity model (14 to 20 weeks, one hour per week, face to face one to one with a qualified therapist).