Fatigue Investigation Using Digital Outcomes
FIDO
3 other identifiers
observational
122
1 country
6
Brief Summary
This study investigates objective methods to measure and monitor fatigue in patients with post-COVID-19 condition (long COVID) and multiple sclerosis (MS), and includes a group of healthy volunteers for comparison. Fatigue is a common and debilitating symptom of both conditions, but current assessment methods rely mainly on questionnaires, which can be limited by subjectivity and recall bias. The study uses a smartphone application (the FIDO app) together with wearable devices to continuously collect data on fatigue and its fluctuations during daily life, in order to evaluate the potential of digital, objective measures compared to standard assessments. Participation lasts approximately eight weeks and includes two in-person clinic visits along with a continuous data collection phase. At the initial visit, participants complete baseline assessments and questionnaires and are introduced to the study's digital tools. During the following weeks, participants wear two wearable devices continuously (24 hours a day) and use the FIDO app to complete short daily tasks (approximately 7 minutes every two days) and brief questionnaires (approximately 5 minutes per day). All participants collect a stool sample at home at weeks 4 and 8 for gut microbiome analysis, and complete the Fatigue Scale for Motor and Cognitive Functions at week 4. At the final study visit, participants repeat a subset of the baseline assessments, provide feedback on the digital technology used, and return the study devices.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for all trials
Started May 2026
6 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
Study Start
First participant enrolled
May 26, 2026
CompletedFirst Submitted
Initial submission to the registry
August 14, 2026
CompletedFirst Posted
Study publicly available on registry
August 24, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
May 1, 2028
ExpectedStudy Completion
Last participant's last visit for all outcomes
May 1, 2028
August 24, 2026
August 1, 2026
1.9 years
August 14, 2026
August 20, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (4)
Percentage of Expected Smartwatch Wear Time Recorded Over Two Months
Passive compliance with continuous smartwatch data collection, as a measure of feasibility of long-term fatigue monitoring. Participants wear a smartwatch continuously for two months: a Garmin smartwatch (multiple sclerosis group), an Apple Watch (post-COVID-19 condition group), or either device (healthy controls). Expected wear time is the full duration of each participant's individual enrolment (approximately 60 days), so the denominator is calculated per participant rather than as a fixed period; charging periods are not excluded, so values are not expected to reach 100%. Compliance is calculated per participant as recorded wear time divided by expected wear time, multiplied by 100. Values range from 0% to 100%, with higher values indicating greater compliance. Compliance is also compared by group, disease characteristics and demographic factors, and baseline characteristics associated with lower compliance are described.
2 months
Percentage of Expected Armband Activity Monitor Wear Time Recorded Over Two Months
Passive compliance with continuous armband data collection, as a measure of feasibility of long-term fatigue monitoring. Participants wear an armband activity monitor (ActiGraph LEAP) continuously for two months. All participants wear the same device, so compliance can be compared between groups independently of device type. Expected wear time is the full duration of each participant's individual enrolment (approximately 60 days), so the denominator is calculated per participant rather than as a fixed period; charging periods are not excluded, so values are not expected to reach 100%. Compliance is calculated per participant as recorded wear time divided by expected wear time, multiplied by 100. Values range from 0% to 100%, with higher values indicating greater compliance. Compliance is also compared by group, disease characteristics and demographic factors, and baseline characteristics associated with lower compliance are described.
2 months
Percentage of Scheduled Study Application Questionnaires Completed Over Two Months
Active compliance with self-reported data collection, as a measure of feasibility of long-term fatigue monitoring. Participants complete short questionnaires in the study smartphone application (FIDO app) over two months, comprising cognitive and motor fatigue visual analogue scales prompted four times daily at random times, morning and evening sleep surveys daily, and the Fatigue Severity Scale weekly in the multiple sclerosis and healthy control groups. The number scheduled follows each participant's individual enrolment (approximately 60 days). Compliance is calculated per participant as the number of questionnaires completed divided by the number scheduled, multiplied by 100. Values range from 0% to 100%, with higher values indicating greater compliance. Compliance is reported per questionnaire type, compared by group, disease characteristics and demographic factors, and baseline characteristics associated with lower compliance are described. Response latency is also evaluated.
2 months
Percentage of Scheduled Study Application Performance Tasks Completed Over Two Months
Active compliance with task-based data collection, as a measure of feasibility of long-term fatigue monitoring. Participants complete two brief performance tasks in the FIDO app approximately every second day over two months: a cognitive fatigability test (cFAST) and a 30-second finger tapping task, together taking approximately seven minutes. The number scheduled follows each participant's individual enrolment (approximately 60 days). Compliance is calculated per participant as the number of sessions completed divided by the number scheduled, multiplied by 100. A session counts as completed if the participant finishes the full task protocol. Values range from 0% to 100%, with higher values indicating greater compliance. Compliance is reported per task, compared by group, disease characteristics and demographic factors, and baseline characteristics associated with lower compliance are described. Response latency is also evaluated.
2 months
Secondary Outcomes (23)
Discriminative Accuracy of Cognitive Fatigability Test and Finger Tapping Test Performance for Participant Group, Stratified by Fatigue Level
2 months
Reliability and Within-Participant Variability of Cognitive Fatigability Test and Finger Tapping Test Performance
2 months
Agreement Between Cognitive Fatigability Test and Finger Tapping Test Performance and Established Fatigue and Functional Assessments
2 months
Association Between Digital Measurements Derived From Wearable Data and the Fatigue Scale for Motor and Cognitive Functions (FSMC)
2 months
Discriminative Accuracy of Armband-Derived Digital Measurements for Distinguishing Patients From Healthy Controls, Stratified by Fatigue Level
2 months
- +18 more secondary outcomes
Other Outcomes (3)
Autonomic Function and Symptoms in Participants With Multiple Sclerosis, Post-COVID-19 Condition and Healthy Controls
Baseline and 8 weeks
Agreement Between Blood Pressure Estimated From the Armband Activity Monitor and Cuff-Measured Blood Pressure During Clinical Autonomic Testing
Baseline visits
Time From Notification to Completion of Scheduled Study Application Questionnaires and Performance Tasks Over Two Months
2 months
Study Arms (3)
Multiple Sclerosis
Participants with a clinically confirmed diagnosis of multiple sclerosis (MS). This group is monitored using two wearable devices and the FIDO smartphone application over two months. At the initial visit this cohort completes demographic questions and the following assessments: the Fatigue Scale for Motor and Cognitive Functions (FSMC), the Hospital Anxiety and Depression Scale (HADS), COMPASS-31, and the Multiple Sclerosis Impact Scale (MSIS-29). The MSIS-29 is administered to this cohort only.
Long COVID
Participants with a clinically confirmed diagnosis of post-COVID-19 condition (Long COVID). This group is monitored using two wearable devices and the FIDO smartphone application over two months. At the initial visit this cohort completes demographic questions and the following assessments: the Fatigue Scale for Motor and Cognitive Functions (FSMC), the Munich Berlin Symptom Questionnaire (MBSQ), the Bell Disability Scale, the Hospital Anxiety and Depression Scale (HADS), and COMPASS-31. The MBSQ and Bell Disability Scale are administered to this cohort only, and characterise symptom severity and functional impairment.
Healthy controls
This group is monitored using two wearable devices and the FIDO smartphone application over two months. At the initial visit this cohort completes demographic questions and the following assessments: the Fatigue Scale for Motor and Cognitive Functions (FSMC), the Hospital Anxiety and Depression Scale (HADS), and COMPASS-31.
Eligibility Criteria
Multiple sclerosis participants will be recruited through Bellevue Medical Group (BMG) and NeuroPraxis Zürich during routine clinical visits. External patients may also participate if they have a diagnosis from a recognized medical institution. Long COVID participants will be recruited from Klinik Lengg during routine clinical visits. External patients may also participate if they have a diagnosis from a recognized medical institution. Healthy controls will be recruited from the general community in Zurich. Recruitment across all groups will use physical and digital study flyers; the Long Covid Switzerland association will additionally support flyer distribution. Interested individuals may contact the UZH study team by email or phone to learn about study aims and eligibility; those willing and eligible will be directed to a study site.
You may qualify if:
- Confirmed diagnosis of MS (by neurologist) or Long COVID (by medical doctor).
- Smartphone ownership.
- Provide written informed consent.
- Fluent in German or English.
- Smartphone ownership.
- Provide written informed consent.
- Fluent in German or English.
You may not qualify if:
- Concomitant medication affecting fatigue or ANS such as antidepressants prescribed or adjusted 1 month before the initial visit.
- Unable to provide informed consent.
- Unwilling or unable to comply with the study protocol.
- Pregnancy or lactation.
- For controls: Diagnosis of any chronic disorders or diseases that may affect fatigue or ANS.
- For MS: Additional comorbidities that may affect fatigue or ANS such as autoimmune disease and cardiovascular disease.
- For long COVID: Additional comorbidities diagnosed prior to the first acute COVID-19 infection that may affect fatigue or ANS such as autoimmune disease and cardiovascular disease.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Liliana Barrioslead
- University of Zurichcollaborator
- Innosuisse - Swiss Innovation Agencycollaborator
- Insel Gruppe AG, University Hospital Berncollaborator
- ETH Zurich (Switzerland)collaborator
- Centre Suisse d'Electronique et de Microtechnique (CSEM), Switzerlandcollaborator
Study Sites (6)
Neurozentrum Basel Messeturm
Basel, Basel, 4058, Switzerland
Bellevue Medical Group - Neurozentrum Sternen / Neurozentrum Bellevue
Zurich, Canton of Zurich, 8001, Switzerland
University of Zurich
Zurich, Canton of Zurich, 8001, Switzerland
NeuroPraxis Zürich GmbH
Zurich, Canton of Zurich, 8006, Switzerland
Bellevue Medical Group - Neurozentrum Seefeld
Zurich, Canton of Zurich, 8008, Switzerland
Klinik Lengg AG
Zurich, Canton of Zurich, 8008, Switzerland
Related Publications (2)
Gashi S, Oldrati P, Moebus M, Hilty M, Barrios L, Ozdemir F; PHRT Consortium; Kana V, Lutterotti A, Ratsch G, Holz C. Modeling multiple sclerosis using mobile and wearable sensor data. NPJ Digit Med. 2024 Mar 11;7(1):64. doi: 10.1038/s41746-024-01025-8.
PMID: 38467710BACKGROUNDBarrios L, Amon R, Oldrati P, Hilty M, Holz C, Lutterotti A. Cognitive fatigability assessment test (cFAST): Development of a new instrument to assess cognitive fatigability and pilot study on its association to perceived fatigue in multiple sclerosis. Digit Health. 2022 Aug 25;8:20552076221117740. doi: 10.1177/20552076221117740. eCollection 2022 Jan-Dec.
PMID: 36046638BACKGROUND
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Central Study Contacts
Study Design
- Study Type
- observational
- Observational Model
- COHORT
- Time Perspective
- PROSPECTIVE
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR INVESTIGATOR
- PI Title
- Principal Investigator
Study Record Dates
First Submitted
August 14, 2026
First Posted
August 24, 2026
Study Start
May 26, 2026
Primary Completion (Estimated)
May 1, 2028
Study Completion (Estimated)
May 1, 2028
Last Updated
August 24, 2026
Record last verified: 2026-08