An observational study in Myasthenia Gravis and Fatigue, sponsored by Leiden University Medical Center. Recruiting at 2 sites in Netherlands. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-08.
Sponsored by Leiden University Medical Center · Observational
This study will make use of a cross-sectional design of MG patients and non-MG participants to quantitatively assess key MG symptoms, and to explore the applicability of machine learning algorithms to their measurement.
Due to the cross-sectional design, participants will only have to visit Leiden University Medical Center (LUMC) once. For patients already treated in the LUMC, we will try to align this visit with a standard clinical appointment.
After inclusion, all baseline data, consisting of demographics, clinical history and a number of questionnaires (four for MG participants, three for non-MG participants), will be collected. The symptom-specific assessments are performed in a standard order, with the most fatiguing task (i.e. proximal arm fatigue static assessment) last. We estimate the visit will take a total of 60 minutes.
This study is considered to be low risk. Withholding pyridostigmine for a limited period is part of standard care of MG (before investigations or clinical assessments) and does not affect long term clinical outcome. MG participants will consent to withhold pyridostigmine for 12 hours prior to the study visit if they are on this treatment and restart it after the visit. As this is a non-interventional, observational study where only questionnaire-based and non-contact digital data are being collected, the only source of marginal risk relates to data protection and confidentiality, including arrangements for the transfer and storage of data. Given it would not be possible to deidentify the digital audio or video data while maintaining the requisite integrity for data analysis, we will seek explicit consent for the sharing of this information in this identifiable format.
330 studies on the registry are indexed under Myasthenia Gravis; 144 are open to participants now.
This study's planned enrollment of 225 is above the median of 130 across 105 observational studies indexed under Myasthenia Gravis.
Browse Myasthenia Gravis studies →Leiden University Medical Center is the lead sponsor of 334 studies on the registry; 110 are open to participants now.
Counted across the registry records on this site, refreshed daily.
We aim to include 150 patients with Myasthenia Gravis, recruited from the national Dutch-Belgia MG registry, the patient organisation 'Spierziekten Nederland' or identified by the clinical team of Leiden University Medical Center (LUMC).
Non-MG participants are preferentially sampled from friends and family of enrolled MG patients. The highest preference will be same-household family members, lowest preference will be non-household non-family members. This acts as both a natural source of control participants and a natural control for any environmental confounders. Furthermore, non-MG participants will be recruited separately by placing flyers in crowded areas in the LUMC.
Inclusion Criteria:
Inclusion Criteria for MG participants only:
Inclusion Criteria for non-MG participants only
Exclusion Criteria:
Exclusion Criteria for MG participants only:
Exclusion Criteria for non-MG participants only:
1. Limitation of upper limb mobility or speech impairment of any cause.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
MG patients with at least one of the symptoms of interest (i.e. dysarthria, dysphonia, proximal arm fatigue and/or ptosis). We aim to include 150 patients with Myasthenia Gravis.
Non-MG participants that do not have a medical history of any of the symptoms of interest. We aim to include 75 controls.
Differentiating between MG-patients and non-MG participants using digital features of dysarhtria, dysphonia, proximal arm fatigue and ptosis.
Using machine-learning algorithms.
Time frame: Assessed at a single time point during outpatient visit
Correlating digital features of dysarthria, dysphonia, proximal arm fatigue and ptosis in MG patients with disease severity as measured by the MGC score.
Myasthenia Gravis Composite (MGC) is scored on an ordinal scale with four possible categories and weighted and consists of 10 items with a total score of 0-50; a higher score indicating more severe disease.
Time frame: Assessed at a single time point during outpatient visit
Correlating digital features of dysarthria, dysphonia, proximal arm fatigue and ptosis in MG patients with the impact of MG on daily activities as measured by the MG-ADL.
MG Activities of Daily Living (MG-ADL) consists of 8 items with a total score of 0-24; a higher score indicating more severe disease. .
Time frame: Assessed at a single time point during outpatient visit
The performance of automated signal processing of speech recordings collected through smartphone microphone for detection of dysarthria and dysphonia compared to clinical assessment.
Clinical assessment by two independent trained speech and language pathologists (SLP) using the Therapy Outcome Measure scale (TOMS) for dysarthria and GRBAS scale (Grade, Roughness, Breathiness, Asthenia and Strain) for dysphonia.
Time frame: Assessed at a single time point during outpatient visit
The performance of automated measurement of proximal arm-fatiguing exercises through computer vision techniques applied to smartphone camera recordings for detection of proximal arm muscle weakness and fatigability compared to clinical assessment.
Clinical assessment by accredited clinicans.
Time frame: Assessed at a single time point during outpatient visit
The performance of automated measurement of ptosis-provoking exercises through computer vision techniques applied to smartphone camera recordings for detection of ptosis compared to clinical assessment.
Clinical assessment by accredited clinicians.
Time frame: Assessed at a single time point during outpatient visit
Correlating digital features of dysarthria, dysphonia, proximal arm fatigue and ptosis in MG patients with their level of fatigue as measured by the CIS-fatigue subscale.
Checklist Individual Strength (CIS-) fatigue subscale consists of 8 questions on fatigue experienced during the previous 2 weeks. Each question is scored on a 7-point Likert scale and a score ≥ 35 indicates severe fatigue. A higher score means more severe fatigue. The total score of the fatigue subscale ranges from 8-56 (the total score of the CIS questionnaire ranges from 20-140).
Time frame: Assessed at a single time point during outpatient visit
Plan to share: No
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