@Diane O'Leary
I think I need to add some context here to the issue of how the UK medical system views the US one.
Firstly we don't even have the same version of the WHO ICD. Having said that its ironic the the UK officially has recognised ME as a neurological disease since 1969 yet the US has not and codes it differently in their version.
Technically we never needed the IOM to make it official that ME is a biological disease in the UK. Yet the BPS crowd has ignored its own agencies for decades so why would our whole system just roll over to a "foreign agency"?
I think you need to understand that when it suits the UK establishment they use the narrative that something carries less weight simply because its from a non British agency not the other way around. In this case they build up a strawman based on the outside view looking in of the "mess of the US healthcare system with millions uninsured, the private insurance industry issue and the demon of big pharma".
They cherry pick and obfuscate partly to use an appeal to authority argument (their own authority) and keep well away from content of an argument that doesn't suit them.
They have already played the narrative that the IOM has lost it credibility by folding to patient pressure and all the usual "militant vocal minority stuff".
When Cochrane was about to withdraw the ME review the wife of a knight of the realm, Sir Simon Wessley who was involved in PACE, tweeted out that Cochrane had lost its way for doing the same. "Bowing to activist pressure".
She is an influential GP and was chair of the Royal College of GPs in the UK until recently. The chaos and scheming that followed led to Cochrane backing off and they now seem to have done a partial about turn.
Secondly the UK system obviously operates as a socialised system.
The US is a privatised system.
Socialised medicine reaches all people "equally". Equally badly, equally well or equally indifferently.
There's is a "healthy" scepticism against privatised medicine for profit in the UK.
When looking at the US system, and the FDA (including the production of food and its legislation etc) UK agencies can have a "protectionist" view against the "right" of everyone to have, not healthcare rights, but healthcare that is free from lobbyist and corporate influence.
It should be "scientifically" driven. UK medics do not simply bow down to US agencies and anyone from the UK that has been to the US and watched tv sits in amazement at the the commercials that seems to be longer than the TV shows that constantly bombard people with their "right" to the latest miracle pill for anything one can think of.
Its a fair criticism to say that when the right to a treatment is built into the psyche of the people there is going to be an extreme pressure on certain agencies, clever marketing, the issue of the revolving door between health authorities and private interests.
Without making any claims over whether a private or socialized system is better these are the complexities that we are left with when viewing one or another from the outside.
You rightly state that an organisation like the IOM should carry scientific weight around the world but equal argument can be made for Oxford University or Imperial College London, both of which have prominent BPSers.
How about the Lancet or the BMJ? Look how appalling they have been over the whole PACE saga. The name of a journal or an organisation carries no weight or is at least neutralised if one can just cite an opposing view from another "prestigious" journal or organisation. The perfect example is how the BPS crowd are using the HRA response. It is claimed as a clean bill of health for PACE so who cares about the IOM in America that crazy country that doesn't even regulate guns, is oftne the UK establishment stance. That's not a direct quote from them but sometimes Americans think the outside world hangs on the every word of pronouncements that come out of American agencies, when its quite the opposite often.
This is how the BPS crowd has done this for so long. Its not a content by content evidenced argument tactic, its confusion and obfuscation.
I note however that you talked about the IOM yet didn't touch on the DSM. The DSM is American, although in the UK officially we don't use the DSM it has massive influence and enables justification of psychiatric pseudoscience all around the world.
The APA is American, yet there hasn't been a squeak out of either of them about the issues surrounding how dubious alternatives acronyms for ME and many other diseases have been in order to swallow them up into their camp.
There's is no official statement from the DSM or the APA.
Currently the psyche of "protection" from dubious privately driven motives in medicine affecting the bottom line of the UK socialized system is adversely affecting the actual science around ME and allowing it to be polluted. Not because the people within the BPS crowd are scientifically driven but because they are being enabled by the pscyhe ingrained into UK medicine.
Obviously that's not the only reason, there are issues of withholding and rationing treatment and testing within socialised medicine (especially if its deemed unnecessary) which basically rolls over into medical science and the development of good science within medicine.
This has left a void for psychiatric pseudoscience to flourish in.
They have been left to get on with it as the high priests and as you say no one is really looking beneath the covers.
Now what we are left with is years of policy that has saved money week to week, careers staked on pride, poor education and gatekeeper practice, by default and design.
The DWP is the government, the NHS is the government, NICE is the government, etc. They are all in it together and they all stand to go down with it if the ship sinks.