An interventional study of $5 gift card and $100 monthly drawing in Screening, sponsored by University of California, San Francisco. Recruiting at 2 sites in United States. Open to participants aged 50 Years and older. Per ClinicalTrials.gov, last updated 2026-09-09.
Sponsored by University of California, San Francisco · Not applicable, Interventional, and Screening
This is a randomized trial to assess whether offering a financial incentive will improve the response rate to a telephone survey. Three incentive approaches will be compared: a $5 gift card, entry into a monthly $100 drawing, or no incentive.
This is a sub-trial nested within a larger randomized trial called GSEARCH. The parent trial evaluates whether telemedicine glaucoma screening is more effective for detecting undiagnosed glaucoma cases compared with education alone or delayed intervention, with the final outcomes assessed via a follow-up telephone surveys at 3 months and 12 months. In this sub-study, we will assess whether adding an incentive improves the survey response completion rate. Participants enrolled in the parent GSEARCH trial will be eligible. Participants will be randomized to one of three incentive approaches, offered by telephone at the time of the follow-up survey ($5 gift card, entry into a monthly $100 drawing, or no incentive). The primary outcome will be completion of the telephone survey.
1,419 studies on the registry are indexed under Glaucoma; 223 are open to participants now.
This study's planned enrollment of 2,000 is above the median of 61 across 964 interventional studies indexed under Glaucoma.
Browse Glaucoma studies →University of California, San Francisco is the lead sponsor of 2,169 studies on the registry; 372 are open to participants now.
Of its 267 completed or terminated interventional studies of FDA-regulated products, 202 (76%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
- Participating in GSEARCH trial
Exclusion Criteria:
- Patients without a valid phone number
Other: $5 gift card
Other: $100 monthly drawing
No incentive is offered for participation in the 3-month survey call.
A $5 gift card is offered as an incentive to participation in the 3-month survey call.
Entry into monthly drawing for $100 gift card is offered as an incentive to participation in the 3-month survey call.
Survey completion
Time frame: One month after the outreach call is completed
Not enrolling at this site.
Plan to share: Yes — treatment arm, age, gender, survey completion
Time frame: After publication of the primary papers.
Access criteria: Researchers interested in accessing data from this project will submit requests to the investigators following instructions available at the repository. The study's co-PIs will approve requests with clear research questions and processes in place to ensure secure storage of images.
No publications or documents are linked to this record.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
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