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NCT04426331 · ClinicalTrials.gov registry record · NA
Vouchers to Increase Uptake of Already Free Eye Care
A NA study, sponsored by Johns Hopkins University.
- Completed
- Registry status
- NA
- Development phase
- 739
- Enrollment target
NCT04426331: Completed NA study, sponsored by Johns Hopkins University.
NCT04426331 is a NA study that has completed, run by Johns Hopkins University. The registered enrollment target is 739 participants, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (47% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT04426331, a NA study, has completed, sponsored by Johns Hopkins University.
- COMPLETED
- Registry status
- NA
- Development phase
- 739 participants
- Enrollment target
Study Summary
This study was intended to test if reframing an offer for a free follow-up eye examination could increase uptake within ongoing community-based screening program for low-income and minority populations in Baltimore City. This study evaluated the effect of offering participants a physical voucher they were told was redeemable for free follow-up, relative to simply telling participants that the follow-up appointment would be free of charge. The investigators assessed two forms of vouchers, one with estimated value information, and one without. The underlying hypothesis was that reframing these already free offers would increase uptake by increasing perceived offer value and increasing a sense of regret from not taking advantage of a "good deal."
Primary Outcome
The primary endpoint was attending a follow-up appointment, either on the initially scheduled or on a rescheduled date within 90 days of the date of screening. Individuals who did not meet this endpoint either stated that they were not interested in follow-up at the screening event itself, cancelled or did not show for their appointments on 3 occasions, stated that they were not interested in follow-up when study staff attempted to reschedule, or did not show for an appointment and could not be
Interventions
- BEHAVIORAL Voucher Without Value Information
- BEHAVIORAL Voucher With Value Information
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 739 participants |
| Start Date | 2017-05-05 |
| Est. Completion | 2019-01-01 |
| Phase | NA |
What the finished NCT04426331 record still lists
NCT04426331 is an interventional study that assigns participants to a tested intervention. The registered 739 participants enrollment target is mid-sized for trials with a published cap, below the 1,404-participant average among 58,714 other NA trials with a reported enrollment target (47% lower).
The record links to 0 conditions, and to 2 interventions - of which Voucher Without Value Information is the first listed.
NCT04426331 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT04426331 about?
NCT04426331 is a clinical study titled "Vouchers to Increase Uptake of Already Free Eye Care". This study was intended to test if reframing an offer for a free follow-up eye examination could increase uptake within ongoing community-based screening program for low-income and minority populations in Baltimore City. This study evaluated the effect of offering participants a physical voucher the...
What is the current status of trial NCT04426331?
This trial is currently completed. It is a NA study. The enrollment target is 739 participants. The study started on 2017-05-05. Estimated completion is 2019-01-01.
What interventions are being tested in trial NCT04426331?
The interventions under investigation include: Voucher Without Value Information (BEHAVIORAL), Voucher With Value Information (BEHAVIORAL).
Who is sponsoring clinical trial NCT04426331?
This trial is sponsored by Johns Hopkins University, which has 1,448 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT04426331's enrollment target sits among peer trials
739 145th of 2000 higher than 1,856 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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