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NCT04951310 · ClinicalTrials.gov registry record · NA
COVID-19 Vaccinations With a Sweepstakes
A NA study, sponsored by University of Pennsylvania.
- Completed
- Registry status
- NA
- Development phase
- 3,827,656
- Enrollment target
NCT04951310: Completed NA study, sponsored by University of Pennsylvania.
NCT04951310 is a NA study that has completed, run by University of Pennsylvania. The registered enrollment target is 3,827,656 participants, above the 1,338-participant average among 58,714 other NA trials with a reported enrollment target (285973% higher). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04951310, a NA study, has completed, sponsored by University of Pennsylvania.
- COMPLETED
- Registry status
- NA
- Development phase
- 3,827,656 participants
- Enrollment target
Study Summary
To reach herd immunity for COVID-19, experts estimate that 70% of the population will need to be vaccinated. However, vaccination rates have begun to slow down in the United States. The investigators will partner with Philadelphia to launch a COVID-19 vaccination sweepstakes, in which residents will be eligible to win if they have received at least one dose of the COVID-19 vaccine prior to a given drawing. Drawings will be held every two weeks; multiple prizes of various sizes will be awarded in each drawing. Half of the prizes in each size category in each drawing will be awarded to residents of a zip code that is randomly selected from a pre-defined list of under-vaccinated zip codes (this zip code will be announced at the start of each 2-week drawing period), the other half will be awarded to residents outside of that selected zip code. The investigators will analyze vaccination rates in Philadelphia as compared with neighboring regions before, during, and after the specified time period, as well as analyze vaccination rates in the three selected zip codes compared to the other zip codes that could have been targeted (the residual set of under-vaccinated zip codes) to determine the effectiveness of the sweepstakes at encouraging vaccinations.
Primary Outcome
The primary outcome is the weekly vaccinations (per 100k residents) for residents receiving a first dose of a COVID-19 vaccination in each zip/county/city, relative to the control group. The vaccination data was measured by local health departments and the residency data was measured by the U.S. Census. The investigators included data from 5 weeks of pre-intervention, 6 weeks of intervention, and 4 weeks of post-intervention. Weekly Vaccinations per 100k Residents = 100,000 \* Total residents re
Interventions
- BEHAVIORAL Philly Vax Sweepstakes
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 3,827,656 participants |
| Start Date | 2021-06-07 |
| Est. Completion | 2021-08-14 |
| Phase | NA |
What the finished NCT04951310 record still lists
NCT04951310 is an interventional study that assigns participants to a tested intervention. Its 3,827,656 participants enrollment target places it among the larger protocols in the corpus, above the 1,338-participant average among 58,714 other NA trials with a reported enrollment target (285973% higher).
The record links to 0 conditions, and to 1 intervention - of which Philly Vax Sweepstakes is the first listed.
NCT04951310 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04951310 about?
NCT04951310 is a clinical study titled "COVID-19 Vaccinations With a Sweepstakes". To reach herd immunity for COVID-19, experts estimate that 70% of the population will need to be vaccinated. However, vaccination rates have begun to slow down in the United States. The investigators will partner with Philadelphia to launch a COVID-19 vaccination sweepstakes, in which residents will...
What is the current status of trial NCT04951310?
This trial is currently completed. It is a NA study. The enrollment target is 3,827,656 participants. The study started on 2021-06-07. Estimated completion is 2021-08-14.
What interventions are being tested in trial NCT04951310?
The interventions under investigation include: Philly Vax Sweepstakes (BEHAVIORAL).
Who is sponsoring clinical trial NCT04951310?
This trial is sponsored by University of Pennsylvania, which has 1,423 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04951310's enrollment target sits among peer trials
3,827,656 1st of 2000 higher than 2,000 of 2,000 other NA trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other NA 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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