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Cited by 62Psychosomatic Disorders and Their TreatmentsMultiple Sclerosis Research StudiesClinical Reasoning and Diagnostic Skills

Functional neurological disorder and multiple sclerosis: a systematic review of misdiagnosis and clinical overlap

Open access
Walzl, Dennis, Solomon, Andrew J., Stone, Jon·2022·Journal of Neurology
DOI 10.1007/s00415-021-10436-6PMC PMC8782816
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Abstract

Multiple sclerosis (MS) and functional neurological disorder (FND) are both diagnostically challenging conditions which can present with similar symptoms. We systematically reviewed the literature to identify patients with MS who were misdiagnosed with FND, patients with FND who were misdiagnosed with MS, and reports of patients with both conditions. In addition to FND, we included studies of patients with other functional and psychiatric disorders where these caused symptoms leading to investigation for or a diagnosis of MS, which in a different context would likely have been labeled as FND. Our review suggests that MS is one of the most common causes of misdiagnosis of FND and vice versa. We discuss the clinical errors that appear to result in misdiagnoses, such as over-reliance on psychiatric comorbidity when making a diagnosis of FND or over-reliance on neuroimaging for the diagnosis of MS, and practical ways to avoid them. Comorbidity between these two conditions is also likely common, has been poorly studied, and adds complexity to diagnosis and treatment in patients with both MS and FND. Misdiagnosis and comorbidity in a landscape of emerging evidence-based treatments for both MS and FND are issues not only of clinical importance to the care of these patients, but also to treatment trials, especially of MS, where FND could be a hidden confounder.

AI snapshot

Written from the paper’s full text.

TL;DR

This systematic review finds that multiple sclerosis (MS) and functional neurological disorder (FND) are not infrequently mistaken for one another and may coexist, with errors driven by over-reliance on psychiatric comorbidity for FND or neuroimaging for MS. It argues these misdiagnoses and comorbidity matter clinically and as potential confounders in MS trials.

Key findings

  • In FND cohort studies, the overall misdiagnosis rate is probably 1–4%, and around 10% of these misdiagnoses may be MS-related—i.e., around 0.1–0.4% of people with FND.
  • In MS cohorts, the frequency of MS misdiagnosis for all conditions ranged from 4 to 36%; among misdiagnosed patients, functional or psychiatric disorders made up between 5 and 51%.
  • Comorbidity is poorly studied but reported: 32/252 (13%) MS outpatients had symptoms only “somewhat” or “not at all” explained by MS; 12/371 (3%) rapid access visits were “non-organic”; one unpublished abstract reported 7.5% of 120 German MS patients had inconsistent findings.
  • One study found 31% of patients misdiagnosed with MS experienced unnecessary morbidity, most commonly from unnecessary immunomodulatory therapy and treatment side-effects.

Methods

  • Systematic review of English-language MEDLINE studies from 1965 to April 2020 using search terms for diagnostic error/misdiagnosis and MS/FND synonyms; 512 abstracts were screened, case reports excluded, and references hand-searched.
  • Included studies focused on diagnostic change between MS and FND or their comorbidity, plus studies of other functional/psychiatric disorders where symptoms led to MS investigation or diagnosis; findings were summarized narratively with tables.

Limitations

  • Stated: reliable frequency estimates are difficult because of heterogeneity in design, outcome measures, diagnostic criteria, and terminology; FND cohort studies focused on diagnosis are uncommon; comorbidity data are scant and poorly researched.
  • Stated/evident: many included MS misdiagnosis studies predate MRI incorporation into MS diagnostic criteria in 2001 and may be less representative; one comorbidity estimate comes from an unpublished conference abstract.
  • Evident from the text: no meta-analysis or formal risk-of-bias assessment is described, and several estimates rely on retrospective records or self-report.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1007/s00415-021-10436-6

Cites

60 of 60 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

37 of 88 cited sources checked · 18 supported · 1 flagged · accuracy not yet measured

  • Premisecitation

    In previous studies by the authors, when people who have MS are initially misdiagnosed, FND is often one of the conditions for which it is mistaken.

    “In several previous studies, we noticed that when people who have MS are initially misdiagnosed, FND is often one of the conditions for which it is mistaken [6]; and when people with FND are misdiagnosed, often the erroneous diagnosis is MS [7].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [6] Solomon AJ, Bourdette DN, Cross AH et al (2016) The contemporary spectrum of multiple sclerosis misdiagnosis. Neurology 87:1393–1399 source

      The Abstract and Results describe patients incorrectly diagnosed with MS, not people with MS initially diagnosed with FND. The Abstract lists conversion or psychogenic disorders among their alternative diagnoses (12 of 110), so this source reports the reverse direction of misdiagnosis from the one attributed to it by citation [6]. (LLM, conf=0.90)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Premisecitation

    Misdiagnosis of MS or FND causes harm to patients, most generally in the form of a delay to diagnosis and initiation of proper treatment.

    “Misdiagnosis of MS or FND causes harm to patients, most generally in the form of a delay to diagnosis and initiation of proper treatment.”
    Quote in the paperSubstantial claim1 of 3 sources checked
    • cites [2] Gelauff J, Stone J, Edwards M, Carson A (2014) The prognosis of functional (psychogenic) motor symptoms: a systematic review. J Neurol Neurosurg Psychiatry 85:220–226 source
    • cites [3] Nielsen G, Buszewicz M, Stevenson F, Hunter R, Holt K, Dudziec M, Ricciardi L, Marsden J, Joyce E, Edwards MJ (2017) Randomised feasibility study of physiotherapy for patients with functional motor symptoms. J Neurol Neurosurg Psychiatry 88:484–490 source

      The Participants section describes how FMS was diagnosed for this study, and the Discussion suggests that earlier physiotherapy might have been more effective. Neither passage addresses misdiagnosis of MS or FND or says that misdiagnosis delayed diagnosis and treatment; searches for those points found no supporting passage. Page numbers were unavailable in our copy. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
    • cites [4] Solomon AJ, Klein E (2013) Disclosing a misdiagnosis of multiple sclerosis: do no harm? Contin Lifelong Learn Neurol 19:1087–1091 source
  • Premisecitation

    The prognosis of patients with FND who are misdiagnosed with MS may improve with more modern evidence-based treatment.

    “Patients with FND who are misdiagnosed with MS have a prognosis similar to MS [2] but which may improve with more modern evidence-based treatment [3].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [3] Nielsen G, Buszewicz M, Stevenson F, Hunter R, Holt K, Dudziec M, Ricciardi L, Marsden J, Joyce E, Edwards MJ (2017) Randomised feasibility study of physiotherapy for patients with functional motor symptoms. J Neurol Neurosurg Psychiatry 88:484–490 source

      The Discussion reports improved symptoms after specialist physiotherapy for patients with functional motor symptoms, supporting the possibility that treatment may improve their outlook. The Participants section says patients had a clinically established functional motor diagnosis; the study does not establish treatment outcomes specifically for patients with FND misdiagnosed with MS. (LLM, conf=0.83)

      Experimental — accuracy not yet measured
  • Premisecitation

    In previous studies by the authors, when people with FND are misdiagnosed, often the erroneous diagnosis is MS.

    “In several previous studies, we noticed that when people who have MS are initially misdiagnosed, FND is often one of the conditions for which it is mistaken [6]; and when people with FND are misdiagnosed, often the erroneous diagnosis is MS [7].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [7] Stone J, Smyth R, Carson A, Lewis S, Prescott R, Warlow C, Sharpe M (2005) Systematic review of misdiagnosis of conversion symptoms and “hysteria.” BMJ 331:989 source
  • Premisecitation

    In a 14-year prospective case-control study of 89 patients with functional limb weakness published in 2019, the only person who had a diagnosis at follow-up which in hindsight may have been a better explanation for their symptoms had been diagnosed with MS.

    “In a 14-year prospective case–control study of 89 patients with functional limb weakness published in 2019, the only person who had a diagnosis at follow-up which in hindsight may have been a better explanation for their symptoms had been diagnosed with MS. This patient had comorbid FND and MS [18].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [18] Gelauff JM, Carson A, Ludwig L, Tijssen MAJ, Stone J (2019) The prognosis of functional limb weakness: a 14-year case–control study. Brain 142:2137–2148 source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
  • Classified as probably not a substantial claim. 21
  • May combine two claims. 35

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    Both MS and FND are common conditions in neurological practice.

    “They also share a similar epidemiology, with a preponderance of female to male patients, and both are common conditions in neurological practice [1].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [1] Espay AJ, Aybek S, Carson A et al (2018) Current concepts in diagnosis and treatment of functional neurological disorders. JAMA Neurol 75:1132–1141 source

      The Epidemiology of FND section reports that 5.4% of patients in a consecutive series of neurology outpatients had a primary FND diagnosis and concludes that FNDs are common. The supplied passages do not address whether MS is common in neurological practice, so the source supports only the FND part of the attributed claim. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    MS and FND share a similar epidemiology, with a preponderance of female to male patients.

    “They also share a similar epidemiology, with a preponderance of female to male patients, and both are common conditions in neurological practice [1].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [1] Espay AJ, Aybek S, Carson A et al (2018) Current concepts in diagnosis and treatment of functional neurological disorders. JAMA Neurol 75:1132–1141 source

      The Epidemiology of FND section says women make up an estimated 60%–75% of FND patients and that FND is common in neurology clinics. It does not give comparable figures for MS or establish that the two conditions have similar epidemiology or are both common in neurological practice. Page numbers are unavailable in our copy. (LLM, conf=0.86)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    The reasons for diagnostic delay in MS are multifactorial and often involve systemic barriers to healthcare access.

    “The reasons for this are multifactorial, and often involve systemic barriers to healthcare access. Although many studies have reported such diagnostic delay in MS care [8–12], only a few have documented specific misdiagnoses that were responsible for such delays (Table 1).”
    Quote in the paperNot a substantial claim1 of 5 sources checked
    • cites [8] Marrie RA, Cutter G, Tyry T, Hadjimichael O, Campagnolo D, Vollmer T (2005) Changes in the ascertainment of multiple sclerosis. Neurology 65:1066–1070 source
    • cites [9] Kelly SB, Chaila E, Kinsella K, Duggan M, McGuigan C, Tubridy N, Hutchinson M (2011) Multiple sclerosis, from referral to confirmed diagnosis: an audit of clinical practice. Mult Scler J 17:1017–1021 source
    • cites [10] Willumsen JS, Aarseth JH, Myhr K-M, Midgard R (2020) High incidence and prevalence of MS in Møre and Romsdal County, Norway, 1950–2018. Neurol Neuroimmunol Neuroinflamm 7:e713 source
    • cites [11] Kingwell E, Leung AL, Roger E, Duquette P, Rieckmann P, Tremlett H (2010) Factors associated with delay to medical recognition in two Canadian multiple sclerosis cohorts. J Neurol Sci 292:57–62 source
    • cites [12] Fernández O, Fernández V, Arbizu T, Izquierdo G, Bosca I, Arroyo R, García Merino JA, De Ramón E (2010) Characteristics of multiple sclerosis at onset and delay of diagnosis and treatment in Spain (The Novo Study). J Neurol 257:1500–1507 source

  • May combine two claims.

    Premisecitation

    Multiple sclerosis (MS) and functional neurological disorder (FND) are both diagnostically challenging conditions that can present with similar symptoms.

    “Multiple sclerosis (MS) and functional neurological disorder (FND) are both diagnostically challenging conditions which can present with similar symptoms.”
    • Also stated in: § Introduction · plain
      “Multiple sclerosis (MS) and functional neurological disorder (FND) are both diagnostically challenging conditions presenting at times with similarly disabling paroxysmal, fluctuating, and multifocal neurological symptoms.”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [1] Espay AJ, Aybek S, Carson A et al (2018) Current concepts in diagnosis and treatment of functional neurological disorders. JAMA Neurol 75:1132–1141 source

      The Importance passage reports that FND has often been misdiagnosed or diagnosed after lengthy delays, supporting the point about diagnostic difficulty for FND. The Phenomenology and Diagnosis section discusses distinguishing FND from other neurological disorders, but the paper does not address MS specifically or state that MS and FND present with similar symptoms; those parts of the claim are unsupported. (LLM, conf=0.85)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In a 2020 Ukrainian study, 53 patients were initially misdiagnosed before receiving the correct diagnosis of MS, including one (2%) with generalized anxiety disorder and six (11%) with 'other neuropsychiatric disorders'.

    “Similarly, in a 2020 study at a tertiary care center in Ukraine, 53 patients were initially misdiagnosed before receiving the correct diagnosis of MS, including one (2%) with generalized anxiety disorder and six (11%) with “other neuropsychiatric disorders” [16].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [16] Ivaniuk A, Marusich T, Solodovnikova Y, Son A (2020) Is initial misdiagnosis associated with reaching disability milestones in patients with multiple sclerosis? Medicina 56:170 source

  • May combine two claims.

    Premisecitation

    A study across 22 MS centers in Italy published in 2019 included 667 patients referred for suspected MS and followed up for up to three years if their diagnosis remained uncertain. Of 163 patients who did not have MS or clinically isolated syndrome, nine (6%) had psychiatric or functional diagnoses: five had 'psychiatric disorder' and four had fibromyalgia.

    “A study across 22 MS centers in Italy published in 2019 included 667 patients who were referred for suspected MS and followed up for up to three years if their diagnosis remained uncertain. Of 163 patients who did not have MS or clinically isolated syndrome, nine (6%) had psychiatric or functional diagnoses: five had “psychiatric disorder” and four had fibromyalgia [27].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [27] Calabrese M, Gasperini C, Tortorella C et al (2019) “Better explanations” in multiple sclerosis diagnostic workup: a 3-year longitudinal study. Neurology 92:e2527–e2537 source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    A retrospective review of all patients presenting to a Brazilian demyelinating disease center from 1994 to 2013 found that 495 out of 1599 (31%) did not have MS, of whom 108 (22%) had 'other diagnosis', which included psychiatric disorders, although the proportion was not specified.

    “A retrospective review of all patients presenting to a Brazilian demyelinating disease center from 1994 to 2013 found that 495 out of 1599 (31%) did not have MS, of whom 108 (22%) had “other diagnosis”, which included psychiatric disorders, although the proportion was not specified [25].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [25] Bichuetti DB, Falcão AB, de Boulos F, C, de Morais MM, Lotti CB de C, Fragomeni M de O, Campos MF, de Souza NA, Oliveira EML, (2014) The profile of patients followed at the Neuroimmunology Clinic at UNIFESP: 20 years analysis. Arq Neuropsiquiatr 73:304–308 source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In that systematic review, revised diagnoses were reported in 68 out of 123 misdiagnosed patients; the most common were epilepsy (19%), multiple sclerosis (9%), and movement disorders (9%).

    “Revised diagnoses were reported in 68 out of 123 misdiagnosed patients; the most common were epilepsy (19%), multiple sclerosis (9%), and movement disorders (9%) [7].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [7] Stone J, Smyth R, Carson A, Lewis S, Prescott R, Warlow C, Sharpe M (2005) Systematic review of misdiagnosis of conversion symptoms and “hysteria.” BMJ 331:989 source

  • May combine two claims.

    Premisecitation

    When asked to recall alternate diagnoses in such misdiagnosed patients, the fourth most common disorder reported was psychiatric disorder (45%) and the sixth was fibromyalgia (31%).

    “When asked to recall alternate diagnoses in such misdiagnosed patients, the fourth most common disorder reported was psychiatric disorder (45%) and the sixth was fibromyalgia (31%).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [29] Solomon AJ, Klein EP, Bourdette D (2012) “Undiagnosing” multiple sclerosis: the challenge of misdiagnosis in MS. Neurology 78:1986–1991 source

  • May combine two claims.

    Premisecitation

    A 1997 study of 366 patients with a diagnosis of MS referred for a second opinion to Charles Poser found 130 misdiagnosed patients, including 28 (22%) with chronic fatigue syndrome and eight (6%) with 'psychiatric disorder' or 'post-traumatic syndrome'.

    “A 1997 study of 366 patients with a diagnosis of MS referred for a second opinion to Charles Poser found 130 misdiagnosed patients, including 28 (22%) with chronic fatigue syndrome and eight (6%) with “psychiatric disorder” or “post-traumatic syndrome” [32].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [32] Poser CM (1997) Misdiagnosis of multiple sclerosis and β-interferon. Lancet 349:1916 source

  • May combine two claims.

    Premisecitation

    A comprehensive systematic review of 118 studies found psychiatric comorbidities in MS were common; prevalence of diagnosed anxiety and depression were estimated at 21.9 and 23.7%, respectively.

    “A comprehensive systematic review of 118 studies on psychiatric comorbidities in MS found that psychiatric comorbidities were common; in particular, the prevalence of diagnosed anxiety and depression were estimated at 21.9 and 23.7%, respectively [53].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [53] Marrie RA, Reingold S, Cohen J, Stuve O, Trojano M, Sorensen PS, Cutter G, Reider N (2015) The incidence and prevalence of psychiatric disorders in multiple sclerosis: a systematic review. Mult Scler J 21:305–317 source

      The Abstract Results report 118 studies and prevalence estimates of 21.9% for anxiety and 23.7% for depression among population-based studies; the Discussion says psychiatric comorbidity is common in MS. However, the Results (Psychiatric disorders) show that these estimates combine studies using diagnoses with studies using symptom questionnaires. They are not estimates specifically of diagnosed anxiety and depression. (LLM, conf=0.90)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In the Scottish Neurological Symptoms Study (SNSS), 9 out of 209 (4%) patients with a diagnosis of MS or demyelination at baseline had an alternative diagnosis at 18 months follow-up, of whom three (33%) had a functional disorder or psychiatric diagnosis at follow-up (anxiety and chronic fatigue syndrome).

    “In the Scottish Neurological Symptoms Study (SNSS), 9 out of 209 (4%) patients with a diagnosis of MS or demyelination [33] at baseline had an alternative diagnosis at 18 months follow-up, of whom three (33%) had a functional disorder or psychiatric diagnosis at follow-up (anxiety and chronic fatigue syndrome) [34].”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [33] Stone J, Carson A, Duncan R et al (2011) Which neurological diseases are most likely to be associated with “symptoms unexplained by organic disease.” J Neurol 259:33–38 source
    • cites [34] Walzl D, Carson AJ, Stone J (2019) The misdiagnosis of functional disorders as other neurological conditions. J Neurol 266:2018–2026 source

      Split into 2 atoms — 1 confirmed, 1 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

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  • May combine two claims.

    Premisecitation

    In a study of comorbidity in MS, 668 patients who also self-reported mental comorbidities experienced a delay to diagnosis of MS and were more likely to have severe, rather than mild, disability two years after diagnosis.

    “A study of comorbidity in patients with MS found that the 668 patients who also self-reported mental comorbidities experienced a delay to diagnosis of MS, and were more likely to have severe, rather than mild, disability two years after diagnosis [54].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [54] Marrie RA, Horwitz R, Cutter G, Tyry T, Campagnolo D, Vollmer T (2009) Comorbidity delays diagnosis and increases disability at diagnosis in MS. Neurology 72:117–124 source

      The Results identify 668 participants with self-reported mental comorbidities, and the Abstract reports both increased diagnostic delay with mental comorbidity and higher odds of severe rather than mild disability. But disability was assessed at diagnosis among participants enrolled within two years of diagnosis—not two years after diagnosis. (LLM, conf=0.90)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Studies of Parkinson's disease are increasingly highlighting FND as a comorbidity, especially in the prodromal period.

    “studies of Parkinson’s disease are increasingly highlighting FND as a comorbidity, especially in the prodromal period [40]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [40] Wissel BD, Dwivedi AK, Merola A et al (2018) Functional neurological disorders in Parkinson disease. J Neurol Neurosurg Psychiatry 89:566–571 source

      The Introduction describes FND co-occurring with Parkinson disease, and the Characteristics of the functional phenotype section reports that FND symptoms preceded PD diagnosis in 26% of the PD-FND cohort. But FND began after PD diagnosis in 57%, so the paper does not support the emphasis on the prodromal period; preceding diagnosis also does not establish that symptoms arose before PD itself. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Premisecitation

    In that 2016 case series, 16 (15%) were diagnosed with fibromyalgia, and 13 (12%) with non-specific or non-localizing neurologic symptoms with abnormal MRI.

    “Also of note, 16 (15%) were diagnosed with fibromyalgia, and 13 (12%) with non-specific or non-localizing neurologic symptoms with abnormal MRI [6].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [6] Solomon AJ, Bourdette DN, Cross AH et al (2016) The contemporary spectrum of multiple sclerosis misdiagnosis. Neurology 87:1393–1399 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Diagnostic criteria for FND based on DSM-5 emphasize finding evidence of clinical incompatibility with recognized diseases, which in practice requires positive signs of internal inconsistency and incongruity.

    “Diagnostic criteria for FND based on DSM-5 emphasize finding evidence of clinical incompatibility with recognized diseases, which in practice requires the presence of positive signs of internal inconsistency and incongruity [1]”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [1] Espay AJ, Aybek S, Carson A et al (2018) Current concepts in diagnosis and treatment of functional neurological disorders. JAMA Neurol 75:1132–1141 source

  • May combine two claims.

    Premisecitation

    In one study, 31% of patients misdiagnosed with MS experienced unnecessary morbidity as a result of misdiagnosis, most commonly due to unnecessary immunomodulatory therapy and treatment side-effects.

    “In one study, 31% of patients misdiagnosed with MS experienced unnecessary morbidity as a result of misdiagnosis, most commonly due to unnecessary immunomodulatory therapy and treatment side-effects [6].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [6] Solomon AJ, Bourdette DN, Cross AH et al (2016) The contemporary spectrum of multiple sclerosis misdiagnosis. Neurology 87:1393–1399 source

  • May combine two claims.

    Premisecitation

    FND and functional disorders are known for a high frequency of psychiatric comorbidity and disturbances in emotional regulation that have also been found in MS.

    “Nonetheless, FND and functional disorders also are known for a high frequency of psychiatric comorbidity as well as disturbances in emotional regulation that have also been found in MS [56].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [56] Harel Y, Barak Y, Achiron A (2007) Dysregulation of affect in multiple sclerosis: new phenomenological approach. Psychiatry Clin Neurosci 61:94–98 source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Premisecitation

    The scientific landscape around FND has changed considerably in the last 10 years.

    “However, the scientific landscape around FND has changed considerably in the last 10 years [1].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [1] Espay AJ, Aybek S, Carson A et al (2018) Current concepts in diagnosis and treatment of functional neurological disorders. JAMA Neurol 75:1132–1141 source

      The Treatment section describes emerging evidence for FND treatments, and the Physical Treatment of FND section says a greater role for physical therapy has recently been recognized. These passages support a changing scientific landscape, but the paper does not establish that the change occurred specifically over the last 10 years. (LLM, conf=0.82)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    When the new diagnosis is a functional disorder, the neurologist may feel less equipped to help than with an MS diagnosis.

    “This is perhaps especially the case when the new diagnosis is one of a functional disorder, when the neurologist may feel less equipped to help than they were with an MS diagnosis [58].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [58] Carson AJ, Stone J, Warlow C, Sharpe M (2004) Patients whom neurologists find difficult to help. J Neurol Neurosurg Psychiatry 75:1776–1778 source

      The Results report that neurologists rated patients with symptoms poorly explained by organic disease as more difficult to help than those with fully explained symptoms. The paper lists multiple sclerosis among the diagnoses in its sample, but it does not specifically compare functional-disorder diagnoses with MS diagnoses or assess how equipped neurologists felt to help each group. (LLM, conf=0.84)

      Experimental — accuracy not yet measured

  • May combine two claims.

    Findingreasoning

    While these studies demonstrate low absolute numbers of patients with MS who were initially misdiagnosed as having FND, large cohort studies of FND focused on diagnosis are uncommon.

    “While these studies demonstrate low absolute numbers of patients with MS who were initially misdiagnosed as having FND, large cohort studies of FND focused on diagnosis are uncommon.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    Unlike MS cohort studies, FND cohort studies employed a restricted and more accurate definition of FND, whereas in the MS literature, functional disorders and psychiatric disorders are often grouped together with inconsistent terminology.

    “Unlike MS cohort studies, these studies employed a restricted and more accurate definition of FND, whereas in the MS literature, functional disorders and psychiatric disorders are often grouped together with inconsistent terminology.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingcitation

    Our review suggests that MS is one of the most common causes of misdiagnosis of FND and vice versa.

    “Our review suggests that MS is one of the most common causes of misdiagnosis of FND and vice versa.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingcitation

    The topic of FND and MS comorbidity is poorly researched, but the studies available suggest it occurs.

    “In conclusion, the topic of FND and MS comorbidity is poorly researched, but the studies we have do suggest it occurs”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingreasoning

    MS and FND are common conditions that are not infrequently mistaken for one another, and may co-exist more often than is currently acknowledged.

    “MS and FND are common conditions that are not infrequently mistaken for one another, and which may co-exist more often than is currently acknowledged.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Both FND and MS can result in disabling paroxysmal or fluctuating neurological symptoms in young adults.
    • Rests on an assumption: Accurate diagnosis in both FND and MS relies on a skilled clinical assessment.
    • Rests on an assumption: There remains no highly specific biomarker for either MS or FND.

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Misdiagnosis of FND in patients who have MS may result in irreversible disability as a consequence of delays in the initiation of disease modifying therapy (DMT).

    “Misdiagnosis of FND in patients who have MS may result in irreversible disability as a consequence of delays in the initiation of disease modifying therapy (DMT).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    DMTs carry unnecessary side-effects and risks for patients with FND who are misdiagnosed with MS.

    “However, DMTs carry unnecessary side-effects and risks for patients with FND who are misdiagnosed with MS.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    In a subsequent prospective cohort study of patients referred to neurology outpatient clinics in Scotland, only 4 (0.4%) out of 1030 patients with FND acquired a subsequent unexpected new diagnosis which better explained the original symptoms, one of whom had MS.

    “In a subsequent prospective cohort study of patients referred to neurology outpatient clinics in Scotland, only 4 (0.4%) out of 1030 patients with FND acquired a subsequent unexpected new diagnosis which better explained the original symptoms, one of whom had MS [17].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [17] Stone J, Carson A, Duncan R et al (2009) Symptoms “unexplained by organic disease” in 1144 new neurology out-patients: how often does the diagnosis change at follow-up? Brain 132:2878–2888 source

  • May combine two claims.

    Premisecitation

    These patients with psychiatric diagnoses had one or more of 'somatoform disorders' (76%), mood disorders (33%), and/or anxiety disorders (11%).

    “These patients with psychiatric diagnoses had one or more of “somatoform disorders” (76%), mood disorders (33%), and/or anxiety disorders (11%) [21].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [21] Brousseau K, Arciniegas D, Carmosino M, Corboy J (2007) The differential diagnosis of Axis I psychopathology presenting to a university-based multiple sclerosis clinic. Mult Scler J 13:749–753 source

  • May combine two claims.

    Premisecitation

    Of these patients, 29 (25%) had another neurological disease, none of whom had FND or psychiatric disorders.

    “Of these patients, 29 (25%) had another neurological disease, none of whom had FND or psychiatric disorders (although five “single diagnoses” were not specified).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22] Nielsen JM, Korteweg T, Barkhof F, Polman CH, Uitdehaag BMJ, Polman CH (2005) Overdiagnosis of multiple sclerosis and magnetic resonance imaging criteria. Ann Neurol 58:781–783 source

  • May combine two claims.

    Premisecitation

    In that Dutch study, there were no diagnoses of FND or psychiatric disorders.

    “Conversely, there were no diagnoses of FND or psychiatric disorders in a Dutch retrospective review from 1998 to 2001, where 116 out of 377 (31%) consecutive patients referred for a second opinion to a tertiary MS center had diagnoses other than MS or demyelinating disease [22].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [22] Nielsen JM, Korteweg T, Barkhof F, Polman CH, Uitdehaag BMJ, Polman CH (2005) Overdiagnosis of multiple sclerosis and magnetic resonance imaging criteria. Ann Neurol 58:781–783 source

  • May combine two claims.

    Premisecitation

    In a 1981 study including 69 patients misdiagnosed with MS, 35 (51%) had a functional or psychiatric diagnosis: 16 had a functional disorder, 14 had anxiety/hyperventilation, three had 'hysterical conversion', and two had depression.

    “In a 1981 study including 69 patients misdiagnosed with MS, 35 (51%) had a functional or psychiatric diagnosis: 16 had a functional disorder, 14 had anxiety/hyperventilation, three had “hysterical conversion”, and two had depression [30].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [30] Hankey GJ, Stewart-Wynne EG (1987) Pseudo-multiple sclerosis: a clinico-epidemiological study. Clin Exp Neurol 24:11–19

  • May combine two claims.

    Premisecitation

    In a 2019 study in California, there were no cases of FND among 43 misdiagnosed MS patients referred to two MS tertiary care centers, although there were two cases (5%) of fibromyalgia.

    “In contrast, in a 2019 study in California, there were no cases of FND among 43 misdiagnosed MS patients referred to two MS tertiary care centers, although there were two cases (5%) of fibromyalgia [35].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [35] Kaisey M, Solomon AJ, Luu M, Giesser BS, Sicotte NL (2019) Incidence of multiple sclerosis misdiagnosis in referrals to two academic centers. Mult Scler Relat Disord 30:51–56 source

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Patients who are older, male and do not conform to stereotypes about FND may experience over-diagnosis with disease diagnoses such as MS.

    “Conversely, patients who are older, male and do not conform to stereotypes about FND may experience over-diagnosis with disease diagnoses such as MS.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Up to 20% of patients with dissociative non-epileptic seizures have a history of, or comorbid, epilepsy.

    “up to 20% of patients with dissociative non-epileptic seizures have a history of, or comorbid, epilepsy [39]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [39] Kutlubaev MA, Xu Y, Hackett ML, Stone J (2018) Dual diagnosis of epilepsy and psychogenic nonepileptic seizures: systematic review and meta-analysis of frequency, correlates, and outcomes. Epilepsy Behav 89:70–78 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A case series of four patients with both MS and "hysteria" was published in JAMA in 1980.

    “A case series of four similar patients with both MS and “hysteria” was published in JAMA in 1980 [48].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [48] Caplan LR, Nadelson T (1980) Multiple sclerosis and hysteria: lessons learned from their association. JAMA 243:2418–2421 source

  • May combine two claims.

    Interpretationreasoning

    Psychiatric comorbidity and adverse experience are common and are not of diagnostic value for FND.

    “Such factors may be important in formulation or treatment when present, but are so common that they are not of diagnostic value.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    Making a diagnosis of FND in a patient with a normal MRI and unexplained non-specific neurological symptoms is incorrect and likely to lead to misdiagnosis.

    “Similarly, making a diagnosis of FND in a patient with a normal MRI and unexplained non-specific neurological symptoms is incorrect and likely to lead to misdiagnosis.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationreasoning

    Widespread adoption of MRI for MS diagnosis since completion of the above studies may have resulted in fewer patients with MS being misdiagnosed with FND.

    “Conversely, the widespread adoption of MRI for the diagnosis of MS that has occurred since the completion of a number of the above studies may have resulted in fewer patients with MS having been misdiagnosed with FND.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Of those 44, one had dissociative disorder and another fibromyalgia, and nine had non-specific MRI changes with unclear explanations for their symptoms.

    “Of those, one had dissociative disorder and another fibromyalgia, and nine had non-specific MRI changes with unclear explanations for their symptoms.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [36] de Seabra MML, Abreu PMP, Mendonça MTS, Reis JJCS, Sá MJPM, Guimarães Ferreira Almeida JC (2020) Diagnostic revisions in multiple sclerosis. Clin Exp Neuroimmunol 11:171–175 source

  • May combine two claims.

    Interpretationreasoning

    Clinical assessments required to fulfill the McDonald criteria and specific examination findings in FND (positive signs) increase specificity for diagnosis of each disorder.

    “The clinical assessments required to fulfill the McDonald criteria, and specific examination findings in FND (i.e., positive signs) increase specificity for a diagnosis of each disorder.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Accurate diagnosis in both FND and MS relies on a skilled clinical assessment.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    These studies predate the incorporation of MRI into MS diagnostic criteria in 2001 and may be less representative of contemporary misdiagnosis.

    “Of note, these studies predate the incorporation of MRI into MS diagnostic criteria in 2001 and may be less representative of contemporary misdiagnosis.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    Implications of misdiagnosis of MS in patients with FND include unnecessary treatment of MS and its side-effects and risks, delay to diagnosis and treatment of FND, and psychological harm.

    “The implications of misdiagnosis of MS in patients who have FNDs include unnecessary treatment of MS and its accompanying side-effects and risks, delay to diagnosis and treatment of FND, and psychological harm as a result of misdiagnosis.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    A nationwide cohort study in Denmark did not find a statistically significant increase in diagnostic delay in MS patients with psychiatric comorbidity, but there was a significantly increased mortality.

    “A nationwide cohort study in Denmark did not find a statistically significant increase in diagnostic delay in patients with psychiatric comorbidity, perhaps due to a small number of patients (n = 75), but there was a significantly increased mortality [55].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [55] Thormann A, Sørensen PS, Koch-Henriksen N, Laursen B, Magyari M (2017) Comorbidity in multiple sclerosis is associated with diagnostic delays and increased mortality. Neurology 89:1668–1675 source

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    FND and functional disorders are not synonyms for psychiatric disorder; they are conditions in their own right that do occur without psychiatric comorbidity.

    “It is important to understand that FND and functional disorders are not synonyms for psychiatric disorder; they are conditions in their own right that do occur without psychiatric comorbidity.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationreasoning

    If reliable ways could be found to exclude patients with FND comorbidity, this could lead to better data from trials of MS therapeutic agents.

    “If reliable ways could be found to exclude such patients, this could lead to better data from trials of MS therapeutic agents, a concept that has also been proposed in relation to functional cognitive disorders and dementia trials [59].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [59] McWhirter L, Ritchie C, Stone J, Carson A (2020) Functional cognitive disorders: a systematic review. Lancet Psychiatry 7:191–207 source

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    In patients with MS and FND comorbidity, additional paraclinical testing such as MRI might be necessary to confirm objective evidence of a CNS lesion responsible for symptoms or challenging neurological exam findings.

    “In such patients, additional paraclinical testing, such as MRI, might be necessary to confirm “objective evidence” of a CNS lesion responsible for symptoms or challenging neurological exam findings.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    Improved clinical recognition and broader research efforts focused on the overlap of MS and FND have potentially important consequences for care of patients and for treatment studies in both conditions.

    “Improved clinical recognition and broader research efforts focused on the overlap of these two disabling disorders has potentially important consequences for the care of patients with MS and FND and for treatment studies in both conditions.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Patients can shape their identity around their diagnosis, and it is difficult for neurologists to remove a diagnosis of MS without concern of causing yet more harm to the patient.

    “Patients can shape their identity around their diagnosis, and it is difficult for neurologists to remove a diagnosis of MS without concern of causing yet more harm to the patient [4, 5].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [4] Solomon AJ, Klein E (2013) Disclosing a misdiagnosis of multiple sclerosis: do no harm? Contin Lifelong Learn Neurol 19:1087–1091 source
    • cites [5] Coebergh JA, Wren DR, Mumford CJ (2014) ‘Undiagnosing’ neurological disease: how to do it, and when not to. Pract Neurol 14:436–439 source

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Interpretationnone given

    Difficulties in misdiagnosing FND in a patient with MS are especially magnified if the neurologist failed to validate the patient's symptoms or provide onward treatment.

    “Difficulties will be especially magnified if the neurologist making the original FND diagnosis did so in a way that failed to validate the patient’s symptoms or provide onward treatment.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The diagnosis of a neurodegenerative disease such as MS can have a life-altering psychological effect on patients.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationreasoning

    Identification of patients with MS and FND comorbidity may have a further benefit for MS research.

    “Lastly, the identification of patients with MS and FND comorbidity may have a further benefit for MS research.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    Patients with FND comorbidity may increase "signal to noise ratio" in clinical trials of new therapies for MS with subjectively rated clinical outcome measures.

    “Patients with FND comorbidity may increase “signal to noise ratio” in clinical trials of new therapies for MS with subjectively rated clinical outcome measures.”
    Quote in the paperNot a substantial claim
52 of 52

  • The paper relies on this without support.

    Patients are usually suspected of having MS because they have motor or sensory symptoms.

    “Patients are usually suspected of having MS because they have motor or sensory symptoms.”

  • The paper relies on this without support.

    In many cases, clinicians may have made no diagnosis or focused on a comorbid disorder that they considered relevant or dominant, even though those diagnoses do not encompass the type of motor and sensory symptoms that typically lead to evaluation for or diagnosis of MS.

    “We looked at a broader range of conditions on the grounds that in many cases, it seems likely that clinicians may have made no diagnosis (e.g., non-specific symptoms) or focused on a comorbid disorder that they considered to be relevant or was perhaps dominant, such as anxiety or fibromyalgia, even though those diagnoses do not encompass the type of motor and sensory symptoms that typically lead”

  • The authors state this as an assumption.

    If a sufficient number of patients referred for evaluation of suspected MS are found to have FND, some proportion of such patients are at risk for misdiagnosis of MS.

    “However, if a sufficient number of patients referred for evaluation of suspected MS are found to have FND, it is reasonable to assume that some proportion of such patients are at risk for misdiagnosis of MS.”

  • The paper relies on this without support.

    Both FND and MS can result in disabling paroxysmal or fluctuating neurological symptoms in young adults.

    “Both FND and MS can result in disabling paroxysmal or fluctuating neurological symptoms in young adults”

  • The paper relies on this without support.

    Accurate diagnosis in both FND and MS relies on a skilled clinical assessment.

    “accurate diagnosis in both disorders relies on a skilled clinical assessment”

  • The paper relies on this without support.

    There remains no highly specific biomarker for either MS or FND.

    “There remains no highly specific biomarker for either MS or FND.”

  • The paper relies on this without support.

    Most neurologists specializing in MS recognize that they commonly see patients with an accurate MS diagnosis who also have symptoms or signs suggesting a comorbid functional disorder.

    “Most neurologists specializing in MS recognize that they commonly see patients who clearly have an accurate diagnosis of MS, yet also have symptoms and/or signs which suggest that they have a comorbid functional disorder.”

  • The paper relies on this without support.

    The diagnosis of a neurodegenerative disease such as MS can have a life-altering psychological effect on patients.

    “The diagnosis of a neurodegenerative disease such as MS can have a life-altering psychological effect on patients.”

  • The paper relies on this without support.

    Treatment of FND depends firstly on establishing with the patient that they have a potentially reversible condition related to a problem in the “software” of the nervous system, rather than a “hardware” problem as seen in established MS.

    “The treatment of FND depends firstly on establishing with the patient that they have a condition which is potentially reversible, and related to a problem in the “software” of the nervous system, rather than a “hardware” problem as seen in established MS.”
9 of 9

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Conflicting end years for the Lebanon and Kuwait study

    Minor

    Table 2 gives the data-collection period as 2011-2016, while the prose describes the same study as covering 2011-2015.

  • Psychogenic diagnosis percentage differs from the stated count

    Minor

    The prose reports 19 of 131 patients as 16%, whereas 19/131 is 14.50%. Table 2 reports the same count as 15%.

    Reported 16 · recomputed 14.503817

  • Misdiagnosis percentage is understated in Table 3

    Minor

    The table reports 69 misdiagnosed patients out of 387 as 17%, but the proportion is 17.83%, which rounds to 18% at the printed precision.

    Reported 17 · recomputed 17.829457

3 of 3

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Piliavska K, Maier-Ring D, Dantlgraber M, Schmidt R, Dettmers C (2019) Prevalence of medically unexplained symptoms in multiple sclerosis and their association with psychological factors. In: Annual rehabilitation in multiple sclerosis (rims) conference

Cited by

Sorted by citations

Related

Authors
Walzl, D., Solomon, A. J., & Stone, J.
Affiliations
  • University of Edinburgh (GB)
  • University of Vermont (US)
Corresponding author
Stone, Jon
ORCID
Venue
Journal of Neurology
Publisher
Springer Science and Business Media LLC
Published
2021-02-21
Volume
269
Issue
2
Pages
654-663
ISSN
  • 0012-1037 (ISSN-L)
  • 0340-5354
  • 1432-1459
DOI
10.1007/s00415-021-10436-6
PMC
PMC8782816
OpenAlex
W3131209525
Semantic Scholar
95272ee234349d7fe8100b978dabc4f5de429dfe
Cited by
62
References
60
Citations by year
2026: 7 · 2025: 22 · 2024: 8 · 2023: 16 · 2022: 6 · 2021: 3
FWCI
1.89
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Neurology (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by)
  • Edinburgh Research Explorer (University of Edinburgh) (submittedVersion, cc-by)
Funders
Ruhr-Universität Bochum
Topics
  • Health Sciences › Medicine › Psychiatry and Mental health › Psychosomatic Disorders and Their Treatments
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Multiple Sclerosis Research Studies
  • Health Sciences › Medicine › Family Practice › Clinical Reasoning and Diagnostic Skills
Keywords
conversion disorder, multiple sclerosis, misdiagnosis, clinical overlap, psychiatric comorbidity, neuroimaging, diagnostic errors
MeSH terms
Conversion Disorder, Diagnostic Errors, Humans, Multiple Sclerosis, Nervous System Diseases, Comorbidity, Neuroimaging

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-22.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-22.

Cited sources are checked by gpt-6-sol.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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