Plain-English translation of NCT04834869 on ClinicalTrials.gov ↗ · Source last updated · Translation generated · How we translate trials
This is an independent research study designed to track the safety of COVID-19 vaccines made by different manufacturers — including Pfizer-BioNTech, Moderna, AstraZeneca, and others. The study asks people who have recently received one of these vaccines to report any side effects they experience, both in the short term (days and weeks after vaccination) and over the long term.
Many people hesitate to get vaccinated because they worry about side effects or don't trust information from vaccine makers. This independent study aims to give honest, transparent information about vaccine safety to help people feel more confident in their decision to get vaccinated.
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You would fill out online questionnaires about any side effects you experience after vaccination — first for short-term effects (in the days and weeks after your shot), and then continue to report your health over a longer period as part of an ongoing tracking study. The researchers want to hear from about 30,000 people total across different vaccines to build a clear picture of how safe each one is.
AI-generated summary from trial data · Jun 6, 2026 · Not medical advice
United States
Canada
Croatia
Czechia
Estonia