Development of a diagnostic checklist to identify functional cognitive disorder versus other neurocognitive disorders 2025 Cabreira et al

Abstract

Background
Functional cognitive disorder (FCD) poses a diagnostic challenge due to its resemblance to other neurocognitive disorders and limited biomarker accuracy. We aimed to develop a new diagnostic checklist to identify FCD versus other neurocognitive disorders.

Methods
The clinical checklist was developed through mixed methods: (1) a literature review, (2) a three-round Delphi study with 45 clinicians from 12 countries and (3) a pilot discriminative accuracy study in consecutive patients attending seven memory services across the UK. Items gathering consensus were incorporated into a pilot checklist. Item redundancy was evaluated with phi coefficients. A briefer checklist was produced by removing items with >10% missing data. Internal validity was tested using Cronbach’s alpha. Optimal cut-off scores were determined using receiver operating characteristic curve analysis.

Results
A full 11-item checklist and a 7-item briefer checklist were produced. Overall, 239 patients (143 FCD, 96 non-FCD diagnoses) were included. The checklist scores were significantly different across subgroups (FCD and other neurocognitive disorders) (F(2, 236)=313.3, p<0.001). The area under the curve was excellent for both the full checklist (0.97, 95% CI 0.95 to 0.99) and its brief version (0.96, 95% CI 0.93 to 0.98). Optimal cut-off scores corresponded to a specificity of 97% and positive predictive value of 91% for identifying FCD. Both versions showed good internal validity (>0.80).

Conclusions
This pilot study shows that a brief clinical checklist may serve as a quick complementary tool to differentiate patients with neurodegeneration from those with FCD. Prospective blind large-scale validation in diverse populations is warranted.

Open access

 

Selected quotes

"5. Is there a history of a non-cognitive functional neurological disorder and/or functional somatic disorders (pain, fatigue…)?"

"History of a non-cognitive functional neurological disorder and/or functional somatic disorders
The presence of other symptoms, such as pain, fatigue, dissociation and other functional diagnoses, might be a helpful (although not necessary) lead pointing to FCD."

"Comorbidities, such as non-cognitive FNDs, somatic symptoms (pain, fatigue) and psychological stressors, are common in FCD,15 and potential predisposing and precipitating factors."
Ref 15 is to A unifying theory for cognitive abnormalities in functional neurological disorders, Fibromyalgia and CFS (2018), Mark J Edwards et al.

 

Don't know why they don't go with the old calipers here and go for facial morphology based on differences with typical morphology from locals in their area, like in the good old days. It's not as if this 'checklist' makes any more sense than this. After all, you can 'just know' if someone is good or bad just by looking at them. It's not like this is any different than claiming the same thing about apparent inconsistency. Because obviously real illnesses never fluctuate, or anything like that.

This is a lot like the XKCD comic about standards, except none of those standards have ever worked. But they'll keep inventing them anyway, and pretend like this is legitimate work. Like basically what they took is the mirror reverse of how neurocognitive disorders are assessed. Zero effort, just lazy mediocre nonsense.