Clinical trial NCT05012163: Lottery Incentive Nudges to Increase Influenza Vaccinations
Official title: Lottery Incentive Nudges to Increase Influenza Vaccinations
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Influenza
Vaccination
Health Promotion
Health Behavior
Keywords: Lottery
Financial Incentives
Lead sponsor: National Bureau of Economic Research, Inc.
Sponsor class: OTHER
Collaborators: name: Geisinger Clinic
name: Massachusetts Institute of Technology
name: National Institute on Aging (NIA)
First posted: 2021-08-19
Enrollment: 57581
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Eligible patients will be randomly assigned to one of four arms:

* Pennsylvania Lottery Scratch-Off Financial Incentive
* Certain Cash Payout Financial Incentive
* Reminder / Active Control Arm (No Financial Incentive)
* No Treatment Control Arm
Primary purpose: PREVENTION

Brief summary: In the current study, the study team will explore whether small incentives are effective at promoting flu vaccine uptake. The study is designed to compare the relative efficacy of incentives of equal perceived expected value (EV) or equal implementation costs, to assess whether people are more likely to get vaccinated in response to lotteries with very high payoffs than to small certain cash payout or slightly higher-probability, more moderate payoffs. In particular, given the potential appeal of official state lottery tickets, one study arm will receive a Pennsylvania scratch-off lottery ticket for getting a flu vaccine. A primary hypothesis is that lotteries will outperform simple reminders (encouraging respondents to get the flu shot at their upcoming appointment) and the standard of care, representing the ambient healthcare system and public health campaigns to increase vaccination.

Detailed description: During the 2021-22 flu season, the study team will contact Geisinger patients who have a primary care or specialist appointment scheduled during flu season and encourage them to get a flu shot.

Patients will be randomized into 4 to 9 study arms, depending on a sample size projection completed in August 2021. Arms will test the relative efficacy of a variety of small monetary incentives on flu shot uptake. Incentives may include (a) a $1 Pennsylvania scratch-off lottery ticket (with top prize of $5,000), (b) $1 in cash, (c) entry into a raffle for $5,000 absent upfront odds, (d) entry into a raffle for $5,000, with 1-in-5,000 odds of winning, (d) entry into a raffle for $50, with 1-in-50 odds of winning, and (e) entry into a raffle for $500, with 1-in-500 odds of winning. There will be one no-contact control arm and at least 1 reminder control arm (with additional control arms added given sufficient sample size and additional message versions to be tested).

Included in the study will be current Geisinger patients 18+ years of age with no contraindications for flu vaccine who have an appointment scheduled during the study period with a provider who can administer the vaccine. The primary study outcomes will be the rates of flu vaccination and flu diagnosis during the 2021-22 season by targeted patients.

Eligibility criteria: Inclusion Criteria:

* Aged 18+
* Pennsylvania mailing address listed
* Geisinger primary care provider (PCP) assigned
* Upcoming appointment with PCP or select specialist who stocks and can administer the vaccine during the study period

Exclusion Criteria:

* Has opted out of receiving messages from Geisinger on all modalities being tested

Primary outcomes:
measure: Flu Vaccination at Appointment
timeFrame: 3 days after patient is randomized
Secondary outcomes:
measure: Flu Vaccination Within 7 Days
timeFrame: Within 7 days of when patient is randomized
measure: Flu Diagnosis
timeFrame: During the 2021-22 flu season (Up to 8 months, from the time the patient is randomized through April 30, 2022)
measure: Flu Complications
timeFrame: During the 2021-22 flu season (Up to 11 months, from the time the patient is randomized through July 31, 2022)
Other outcomes:
measure: Flu Vaccination (Among Subject Cohabitants) Within 28 Days
timeFrame: Within 28 days of when the study subject is randomized
measure: Flu Vaccination at Appointment by Gender
timeFrame: 3 days after the patient is randomized.
measure: Flu Vaccination at Appointment by Race
timeFrame: 3 days after the patient is randomized.
measure: Flu Vaccination at Appointment by Ethnicity
timeFrame: 3 days after the patient is randomized.
Locations:
city: Danville
country: United States
facility: Geisinger Clinic
state: Pennsylvania
Study officials:
affiliation: Geisinger Clinic
name: Michelle N Meyer, PhD JD
role: PRINCIPAL_INVESTIGATOR
affiliation: Geisinger Clinic
name: Christopher F Chabris, PhD
role: PRINCIPAL_INVESTIGATOR
References: