I've just been looking at the CCC, and it seems that the core symptoms in the CCC are replicated almost precisely in the new SEID criteria: The only substantial difference in the core symptoms is that pain is a requirement for CCC whereas it isn't a requirement for the SEID. The CCC requires disturbed sleep whereas SEID requires unrefreshing sleep, but unrefreshing sleep is listed as an example of disturbed sleep in the CCC.
CCC core symptoms: Fatigue, PEM, sleep disturbance, pain.
SEID core symptoms: Fatigue, PEM, unrefreshing sleep.
I'm very pleased that pain isn't a core symptom for SEID because many ME patients are not affected by localised pain, and wouldn't complain of pain per se. Most of us experience extreme discomfort, but many would struggle to describe it specifically as pain. Localised pain is related more to fibro.
The CCC also requires cognitive symptoms to be chosen from a list of alternative symptoms and then it requires a range of other non-core symptoms to be chosen. These non-core symptoms introduce a degree of heterogeneity to the CCC.
So, in terms of core symptoms, the new SEID criteria look almost identical to the CCC, but without pain, and considering that, I don't quite understand why there's so much intense discontent being expressed. For clinical criteria, rather than research criteria, the simplicity of the new criteria will perhaps serve patients better than the CCC. Yes, the new name is dodgy, but no two people are ever going to agree about a name, and perhaps we will widely refer to it as ME/SEID. Fukuda is now obsolete, along with the CFS name. Apart from the new name, I'm struggling to understand what's not to like.
I'm slowly reading through the full IOM document, and I haven't seen anything I don't like yet. It includes an interesting history of ME and CFS, including a description of the historic ME outbreaks in the UK, and the outbreaks in the USA that led to the introduction of the CFS moniker. It dismisses the historic claims that the UK ME outbreaks were a case of hysteria. It acknowledges that patients protested about the IOM process and wanted the money to be used for biomedical research instead, and it acknowledges the letter sent from the expert clinicians that demanded the use of the CCC. Still a lot to read.