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Completed Not applicable Interventional Accepts healthy volunteers

Vouchers to Increase Uptake of Already Free Eye Care

ClinicalTrials.gov ID: NCT04426331

Public ClinicalTrials.gov record NCT04426331. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 1, 2026, 2:01 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

Providing Vouchers Redeemable for Already Free Eye Exams To Increase Uptake Among a Low-Income Minority Population: A Randomized Trial

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

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."

Study identification

NCT ID
NCT04426331
Recruitment status
Completed
Study type
Interventional
Phase
Not applicable
Lead sponsor
Johns Hopkins University
Other
Enrollment
739 participants

Conditions and interventions

Eligibility (public fields only)

Age range
50 Years and older
Sex
All
Healthy volunteers
Accepts healthy volunteers

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
May 4, 2017
Primary completion
Dec 31, 2018
Completion
Dec 31, 2018
Last update posted
Jun 15, 2020

2017 – 2019

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Johns Hopkins Hospital - Wilmer Eye Institute Baltimore Maryland 21287

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04426331, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Jun 15, 2020 · Synced Sep 1, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04426331 live on ClinicalTrials.gov.

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