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NCT04331509 · ClinicalTrials.gov registry record
COVID-19 Symptom Tracker
A clinical trial of COVID-19, sponsored by King's College London.
- Active
- Registry status
- 10,000,000
- Enrollment target
- 2
- Study locations
NCT04331509: Active study of COVID-19, sponsored by King's College London.
NCT04331509 is a study of COVID-19 that is active but no longer recruiting, run by King's College London. The registered enrollment target is 10,000,000 participants, above the 4,908-participant average among 298 other COVID-19 trials with a reported enrollment target (203649% higher). The trial reports 2 study locations across 2 states. According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04331509, a study of COVID-19, is active but no longer recruiting, sponsored by King's College London.
- ACTIVE NOT RECRUITING
- Registry status
- 10,000,000 participants
- Enrollment target
- 2
- Study locations
Study Summary
The viral Covid-19 outbreak is now considered a pandemic according to the World Health Organisation (WHO). A free monitoring app 'COVID-19 Symptom Tracker' has been developed to record and monitor the symptoms of the COVID-19 coronavirus infection; tracking in real time how the disease progresses. The app also records how measures aimed at controlling the pandemic including self-isolation and distancing are affecting the mental health and well-being of participants. The data from the study will reveal important information about the symptoms and progress of COVID-19 infection in different people, and why some go on to develop more severe or fatal disease while others have only mild symptoms do not.
Primary Outcome
Self reported as physically healthy (tick box)
Conditions Studied
Interventions
- OTHER No Intervention
Study Locations (2)
Massachusetts
- Massachusetts General Hospital - Boston
London
- King's College London - London
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 10,000,000 participants |
| Start Date | 2020-03-23 |
| Est. Completion | 2026-03-23 |
What the registry record for NCT04331509 still lists
NCT04331509 is an observational study that tracks outcomes without assigning an intervention. Its 10,000,000 participants enrollment target places it among the larger protocols in the corpus, above the 4,908-participant average among 298 other COVID-19 trials with a reported enrollment target (203649% higher).
The record links to 1 condition, with COVID-19 appearing as the primary indexed condition, and to 1 intervention - of which No Intervention is the first listed.
NCT04331509 reports a single indexed study location in Massachusetts, London.
Frequently Asked Questions
What is clinical trial NCT04331509 about?
NCT04331509 is a clinical study titled "COVID-19 Symptom Tracker". The viral Covid-19 outbreak is now considered a pandemic according to the World Health Organisation (WHO). A free monitoring app 'COVID-19 Symptom Tracker' has been developed to record and monitor the symptoms of the COVID-19 coronavirus infection; tracking in real time how the disease progresses. T...
What is the current status of trial NCT04331509?
This trial is currently active not recruiting. The enrollment target is 10,000,000 participants. The study started on 2020-03-23. Estimated completion is 2026-03-23.
What conditions does trial NCT04331509 study?
This clinical trial studies the following conditions: COVID-19.
What interventions are being tested in trial NCT04331509?
The interventions under investigation include: No Intervention (OTHER).
Who is sponsoring clinical trial NCT04331509?
This trial is sponsored by King's College London, which has 5 total clinical trials registered on ClinicalTrials.gov.
Where is trial NCT04331509 being conducted?
This trial has 2 study locations across Massachusetts, London. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
Learn More About Clinical Trials
Similar trials for COVID-19
Matched on the same primary condition, ranked to surface studies in the same phase first, then by recruiting status, no relevance scoring or editorial curation.
Where NCT04331509's enrollment target sits among peer trials
10,000,000 1st of 298 higher than 298 of 298 other COVID-19 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other COVID-19 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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