Conversion DisorderNCT05943652
Observational Study on "Functional Overlay" in Patients With Movement Disorders
An observational study of Conversion Disorder and Parkinson Disease, run by Medical University of Graz at 1 site in Austria.
Trial summary
The goal of this observational study is to learn about functional neurological disorders in patients with common non-functional movement disorders ("functional overlay"). The main questions it aims to answer are: What is the frequency of functional neurological disorders in patients with non-functional movement… Read more about this study
- Who is it for?
- Ages 18 to 18 years
- Conditions the study is for
- Conversion Disorder, Parkinson Disease, Tremor
- What is being tested?
- Neurological examination, Anamnesis and Neuropsychological testing
- Type of treatment
- Injection or infusion
- How many people
- 216 participants
- Where
- 1 siteAustria
- Study dates
- 1 Jan 2023to 30 Jun 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 18 years
- All sexes
- Adult
Study population: Patients with functional and non-functional movement disorders of the Movement Disorders Outpatient Clinic of the Department of Neurology, Medical University of Graz
Who may be able to join
- Functional or non-functional movement disorder
- 18 to 80 years
Who cannot join
- Patient is not able to consent
- Patient is not able to understand / speak German fluently (questionnaires are available only in German)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Austria1 site, 1 recruiting
- Recruiting
Medical University of graz
Graz, Styria, 8010
Daniela Kern, MD, 004331638516051, daniela.eibl@medunigraz.at
About this study
Official title: Prevalence and Clinical Presentation of Functional Neurological Disorders in Patients With Movement Disorders - A Cross-sectional Study in the Movement Disorders Clinic of the Department of Neurology, Medical University of Graz
The goal of this observational study is to learn about functional neurological disorders in patients with common non-functional movement disorders ("functional overlay"). The main questions it aims to answer are:
- What is the frequency of functional neurological disorders in patients with non-functional movement disorders (functional overlay)?
- What are the characteristics of functional neurological disorders in patients with non-functional movement disorders?
Read more
Participants will be examined clinically and electrophysiologically, the examinations consist of:
- a neurological examination
- neuropsychological testing
- electrophysiological tremor diagnostic
- questionnaires about psychological, biological and social risk factors
Researchers will compare patients with functional motor disorders to patients wit non-functional movement disorders to see if they differ from each other regarding the functional symptoms.
Read the detailed description
Functional neurological disorders (FND) are common neurological disorders that are present in up to 16% of patients in neurological outpatient clinics. They are associated with a significant reduction in quality of life, can lead to permanent impairment, and have a poor prognosis, especially if the diagnosis is delayed.
FND have multifactorial causes and risk factors, including psychological stressors, childhood trauma, female gender, psychiatric disorders such as depression, anxiety disorder, or post-traumatic stress disorder, and other functional disorders such as irritable bowel syndrome or chronic pain syndrome. Patients with FND often report additional cognitive complaints ("cognitive fog").
A mismatch of various regulatory mechanisms, a disruption of sensory processing and motor output is assumed to be a central part of the pathogenesis. A characteristic feature of FND is a variability of symptoms according to attention. FND can be intensified by increased attention and weakened by distraction. Positive diagnostic criteria for FND have been established recently, so that by definition FND are no longer a diagnosis of exclusion.
The clinical presentations of FND are diverse and include impaired limb movement control, disturbances in vigilance that may be associated with seizures, and non-motor symptoms. FND often coincide and often coexist with pain, fatigue, sleep disorders, and cognitive disorders. Particularly non-motor functional symptoms are highly debilitating for patients.
The coincidence of "organic" neurological disorders and FND in the same patients ("functional overlay") is probably not uncommon, but has been investigated primarily in patients with Parkinson's Disease and epilepsy, so far. However, it is important to recognize FND in patients with movement disorders in order to treat them adequately and to protect them from incorrect treatment (surgery, unnecessary medication, etc.). However, the basic prerequisite for this is an exploration of the frequency and characteristics of the functional symptoms in movement disorders.
- Conditions
- Conversion Disorder, Parkinson Disease, Tremor, Dystonia
- Being tested
- Neurological examination, Anamnesis, Neuropsychological testing, Questionnaires, Tremor recording
- Keywords
- Accelerometry, Patient Health Questionnaire, Neuropsychology
- Medical subject headings
- Conversion Disorder, Parkinson Disease, Tremor, Dystonia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Neurological examinationDiagnostic test
A neurological examination following a protocol to detect positive signs of functional neurological disorders.
AnamnesisDiagnostic test
A standardized question about the patient´s history. The response time is measured.
Question: "Could you tell me about the problems with the movement disorder you are experiencing?"
Neuropsychological testingDiagnostic test
Neuropsychological cognitive testing including:
- Montreal Cognitive Assessment (MOCA)
- Rey-Osterrieth Complex Figure Test (ROCFT)
- Wechsler Memory Scale IV
- Comprehensive Trail Making Test (CTMT)
- semantic and phonematic fluency tests
QuestionnairesDiagnostic test
- Short Form 36 (SF 36)
- Somatic Symptom Disorder - B Criteria Scale (SSD 12)
- Patient Health Questionnaire 9 (PHQ 9)
- Patient Health Questionnaire 15 (PHQ 15)
- Generalized Anxiety Disorder 7 (GAD 7)
- Fatigue Severity Scale (FSS)
- Psychosomatic Competence Inventory (PSCI)
- Work Ability Index (WAI)
- Level of Personality Functioning Scale
- Toronto Alexithymia Scale
- Levels of Emotional Awareness Scale (short version)
- Certainty About Mental States Questionnaire
- Somatosensoric Amplification Scale
- Personality Inventory for DSM-5 short version (PID5BF+M)
- Childhood Trauma Questionnaire
- European Quality of Life 5 Dimensions 5 Level Version (EQ5D5L)
Tremor recordingDiagnostic test
Accelerometry following a standardized protocol, using a triaxial accelerometer transducer (Biometrics ACL300, Sensitivity 6 100 mV/G, Biometrics Ltd, UK)
| Study group | Role | What they receive |
|---|---|---|
| Parkinson Disease | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording | |
| Idiopathic Dystonia | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording | |
| Essential Tremor | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording | |
| Functional Neurological Disorder | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording | |
| Functional Cognitive Disorder | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording | |
| Alzheimer Disease | Not described Receives: Diagnostic Test: Neurological examination; Diagnostic Test: Anamnesis; Diagnostic Test: Neuropsychological testing; Diagnostic Test: Questionnaires; Diagnostic Test: Tremor recording |
What is being measured
The primary outcome is the main question the study is designed to answer.
Functional neurological symptoms
Diagnosed by positive signs for functional neurological symptoms, as assessed in the neurological examination
Measured: on average 30 minutes
Secondary outcomes (21)
Duration of anamnesis
Duration in seconds of the response to the question: "Could you tell me about the problems with the movement disorder you are experiencing?"
Measured: 1 to 3 minutes
Tremor diagnostic
Sum score of a electrophysiological test battery for psychogenic tremor, a scale from 0 to 10 with higher numbers indicating a higher probability for functional tremor
Measured: up to 20 minutes
Subjective quality of life
European Quality of Life 5 Dimensions 5 Level Version (EQ 5D 5L), results in a 5-digit number that describes the patient's health state
Measured: 5 minutes
Subjective health
Short Form 36 Questionnaire (SF-36), a 36 items questionnaires that results in 8 scales that describe the subjective health state of the patient, higher values indicating better health
Measured: up to 10 minutes
Fatigue
Fatigue severity scale (FSS): 9 item questionnaire with a 7 point Likert scale, higher values indicating more fatigue
Measured: up to 5 minutes
General anxiety
General anxiety disorder scale 7 (GAD-7): a 7 items questionnaire (0 to 21 points, higher values indicating more anxiety)
Measured: 3 minutes
Somatic symptoms
Patient health questionnaire 15 (PHQ 15): a 15 item questionnaire (0 to 30 points, higher values indicating more somatic symptoms)
Measured: 5 minutes
Depression
Patient health questionnaire 9 (PHQ 9): a 9 item questionnaire (0 to 27 points, higher values indicating more depressive symptoms)
Measured: 3 minutes
Psychosomatic Competence
Psychosomatic Competence Inventory (PSCI): a 44 items questionnaire with a 6 point Likert scale, resulting in 6 subscales, higher values indicate higher psychosomatic competence
Measured: up to 10 minutes
Work ability
Work ability index (WAI): 7 item questionnaire, 7 to 49 points, with higher values indicating better work ability
Measured: 5 minutes
Trauma in childhood
Child Trauma Questionnaire (CTQ): 28 items questionnaire, 5 point Likert scale, resulting in 5 subscales with 5 to 25 points, with higher values indicating more trauma experience
Measured: up to 10 minutes
Attachment styles
Experience of Close Relationships-Revised (ECR-RD 12): 12 items questionnaire with a 7 point Likert scale, resulting in 2 subscales
Measured: 5 minutes
Alexithymia
Toronto alexithymia scale (TAS): 26 items questionnaire with a 5 point Likert scale, higher values indicating more alexithymia
Measured: 5 minutes
Personality traits
The Personality Inventory for DSM-5 and ICD-11 Plus Modified (PID5BF + M): a 36 items questionnaire, with a 4 point Likert scale, resulting in 6 subscales
Measured: up to 10 minutes
Personality functioning
Levels of personality functioning scale (LPFS): a 80 items questionnaire, with a 4 point Likert scale, resulting in 4 subscales
Measured: up to 15 minutes
Executive function
Comprehensive trail making test (CTMT)
Measured: up to 10 minutes
Memory
Wechsler Memory Scale
Measured: up to 15 minutes
Visuospatial abilities
Rey-Osterrieth complex figure test
Measured: up to 15 minutes
Functional cognitive symptoms
Incongruence in cognitive tests
Measured: up to 60 minutes
Semantic word fluency
number of animals that can be listed in 2 minutes
Measured: 2 minutes
phonematic word fluency
number of words, that start with the letter "b", that can be listed in 2 minutes
Measured: 2 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted13 Jul 2023
- Study start1 Jan 2023
- Primary completion31 Dec 2025 (estimated)
- Study completion30 Jun 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Conversion DisorderStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Cross-sectional
- Enrolment
- 216 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Medical University of Graz
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05943652
- Sponsor's protocol ID
- 34-509 ex 21/22
- Status last verified
- Sep 2025
- First submitted
- 5 Jul 2023
- Last updated
- 29 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 29 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prevalence and Clinical Presentation of Functional Neurological Disorders in Patients With Movement Disorders - A Cross-sectional Study in the Movement Disorders Clinic of the Department of Neurology, Medical University of Graz
- ClinicalTrials.gov ID
- NCT05943652
- Acronym / sponsor ID
- 34-509 ex 21/22
- Conditions
- Conversion Disorder, Parkinson Disease, Tremor, Dystonia
- Keywords
- Accelerometry, Patient Health Questionnaire, Neuropsychology
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 216 participants (estimated)
- Lead sponsor
- Medical University of GrazUniversity, hospital or other
- Study start
- 1 Jan 2023 (actual)
- Primary completion
- 31 Dec 2025 (estimated)
- Study completion
- 30 Jun 2026 (estimated)
- First posted
- 13 Jul 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this observational study is to learn about functional neurological disorders in patients with common non-functional movement disorders ("functional overlay"). The main questions it aims to answer are:
- What is the frequency of functional neurological disorders in patients with non-functional movement disorders (functional overlay)?
- What are the characteristics of functional neurological disorders in patients with non-functional movement disorders?
Participants will be examined clinically and electrophysiologically, the examinations consist of:
- a neurological examination
- neuropsychological testing
- electrophysiological tremor diagnostic
- questionnaires about psychological, biological and social risk factors
Researchers will compare patients with functional motor disorders to patients wit non-functional movement disorders to see if they differ from each other regarding the functional symptoms.
Detailed description
Functional neurological disorders (FND) are common neurological disorders that are present in up to 16% of patients in neurological outpatient clinics. They are associated with a significant reduction in quality of life, can lead to permanent impairment, and have a poor prognosis, especially if the diagnosis is delayed.
FND have multifactorial causes and risk factors, including psychological stressors, childhood trauma, female gender, psychiatric disorders such as depression, anxiety disorder, or post-traumatic stress disorder, and other functional disorders such as irritable bowel syndrome or chronic pain syndrome. Patients with FND often report additional cognitive complaints ("cognitive fog").
A mismatch of various regulatory mechanisms, a disruption of sensory processing and motor output is assumed to be a central part of the pathogenesis. A characteristic feature of FND is a variability of symptoms according to attention. FND can be intensified by increased attention and weakened by distraction. Positive diagnostic criteria for FND have been established recently, so that by definition FND are no longer a diagnosis of exclusion.
The clinical presentations of FND are diverse and include impaired limb movement control, disturbances in vigilance that may be associated with seizures, and non-motor symptoms. FND often coincide and often coexist with pain, fatigue, sleep disorders, and cognitive disorders. Particularly non-motor functional symptoms are highly debilitating for patients.
The coincidence of "organic" neurological disorders and FND in the same patients ("functional overlay") is probably not uncommon, but has been investigated primarily in patients with Parkinson's Disease and epilepsy, so far. However, it is important to recognize FND in patients with movement disorders in order to treat them adequately and to protect them from incorrect treatment (surgery, unnecessary medication, etc.). However, the basic prerequisite for this is an exploration of the frequency and characteristics of the functional symptoms in movement disorders.
Study design
- Observational model
- Cohort
- Time perspective
- Cross-sectional
- Number of arms
- 6
| Arm | Type | Receives |
|---|---|---|
| Parkinson Disease | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
| Idiopathic Dystonia | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
| Essential Tremor | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
| Functional Neurological Disorder | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
| Functional Cognitive Disorder | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
| Alzheimer Disease | – | Diagnostic Test: Neurological examination, Diagnostic Test: Anamnesis, Diagnostic Test: Neuropsychological testing, Diagnostic Test: Questionnaires, Diagnostic Test: Tremor recording |
Who may qualify
- Ages
- 18 to 18 years
- Sex
- All
- Age groups
- Adult
- Study population
- Patients with functional and non-functional movement disorders of the Movement Disorders Outpatient Clinic of the Department of Neurology, Medical University of Graz
Key inclusion criteria (2 listed)
- Functional or non-functional movement disorder
- 18 to 80 years
Key exclusion criteria (2 listed)
- Patient is not able to consent
- Patient is not able to understand / speak German fluently (questionnaires are available only in German)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Neurological examinationA neurological examination following a protocol to detect positive signs of functional neurological disorders. | Diagnostic test | Alzheimer Disease, Essential Tremor, Functional Cognitive Disorder, Functional Neurological Disorder, Idiopathic Dystonia, Parkinson Disease |
| AnamnesisA standardized question about the patient´s history. The response time is measured. Question: "Could you tell me about the problems with the movement disorder you are experiencing?" | Diagnostic test | Alzheimer Disease, Essential Tremor, Functional Cognitive Disorder, Functional Neurological Disorder, Idiopathic Dystonia, Parkinson Disease |
| Neuropsychological testingNeuropsychological cognitive testing including: * Montreal Cognitive Assessment (MOCA) * Rey-Osterrieth Complex Figure Test (ROCFT) * Wechsler Memory Scale IV * Comprehensive Trail Making Test (CTMT) * semantic and phonematic fluency tests | Diagnostic test | Alzheimer Disease, Essential Tremor, Functional Cognitive Disorder, Functional Neurological Disorder, Idiopathic Dystonia, Parkinson Disease |
| Questionnaires* Short Form 36 (SF 36) * Somatic Symptom Disorder - B Criteria Scale (SSD 12) * Patient Health Questionnaire 9 (PHQ 9) * Patient Health Questionnaire 15 (PHQ 15) * Generalized Anxiety Disorder 7 (GAD 7) * Fatigue Severity Scale (FSS) * Psychosomatic Competence Inventory (PSCI) * Work Ability Index (WAI) * Level of Personality Functioning Scale * Toronto Alexithymia Scale * Levels of Emotional Awareness Scale (short version) * Certainty About Mental States Questionnaire * Somatosensoric Amplification Scale * Personality Inventory for DSM-5 short version (PID5BF+M) * Childhood Trauma Questionnaire * European Quality of Life 5 Dimensions 5 Level Version (EQ5D5L) | Diagnostic test | Alzheimer Disease, Essential Tremor, Functional Cognitive Disorder, Functional Neurological Disorder, Idiopathic Dystonia, Parkinson Disease |
| Tremor recordingAccelerometry following a standardized protocol, using a triaxial accelerometer transducer (Biometrics ACL300, Sensitivity 6 100 mV/G, Biometrics Ltd, UK) | Diagnostic test | Alzheimer Disease, Essential Tremor, Functional Cognitive Disorder, Functional Neurological Disorder, Idiopathic Dystonia, Parkinson Disease |
Primary outcome
Functional neurological symptoms
Time frame: on average 30 minutes
Diagnosed by positive signs for functional neurological symptoms, as assessed in the neurological examination
21 secondary outcomes
Duration of anamnesis
Time frame: 1 to 3 minutes
Tremor diagnostic
Time frame: up to 20 minutes
Subjective quality of life
Time frame: 5 minutes
Subjective health
Time frame: up to 10 minutes
Fatigue
Time frame: up to 5 minutes
General anxiety
Time frame: 3 minutes
Somatic symptoms
Time frame: 5 minutes
Depression
Time frame: 3 minutes
Psychosomatic Competence
Time frame: up to 10 minutes
Work ability
Time frame: 5 minutes
Trauma in childhood
Time frame: up to 10 minutes
Attachment styles
Time frame: 5 minutes
Alexithymia
Time frame: 5 minutes
Personality traits
Time frame: up to 10 minutes
Personality functioning
Time frame: up to 15 minutes
Executive function
Time frame: up to 10 minutes
Memory
Time frame: up to 15 minutes
Visuospatial abilities
Time frame: up to 15 minutes
Functional cognitive symptoms
Time frame: up to 60 minutes
Semantic word fluency
Time frame: 2 minutes
phonematic word fluency
Time frame: 2 minutes
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Sep 2025.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Conversion Disorder and Parkinson Disease, run by Medical University of Graz at 1 site in Austria.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 29 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Austria. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Daniela Kern, MD (004331638516051, daniela.eibl@medunigraz.at), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Functional neurological symptoms (time frame: on average 30 minutes). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Sep 2025; AzTrials last refreshed its copy on 31 Oct 2026.