Lottery Incentive Nudges to Increase Influenza Vaccinations

Influenza Clinical Trial

Official title:

Lottery Incentive Nudges to Increase Influenza Vaccinations

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05012163
• Other study ID #: 2021-0484
• Secondary ID: P30AG034532
• Status: Completed
• Phase: N/A
• Start date: September 4, 2021
• Est. completion date: December 31, 2022

Study information

• Verified date: July 2023
• Source: National Bureau of Economic Research, Inc.
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 57581
• Est. completion date: December 31, 2022
• Est. primary completion date: December 31, 2021
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

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

Related Conditions & MeSH terms

• Health Behavior
• Health Promotion
• Influenza
• Influenza, Human
• Vaccination

Intervention

Behavioral:
• Reminder
Letter, short message service (SMS) text, phone, and/or email
• Financial incentive
Letter, SMS, phone, and/or email
• Lottery
Letter, SMS, phone, and/or email

Locations

Country	Name	City	State
United States	Geisinger Clinic	Danville	Pennsylvania

Sponsors (4)

Lead Sponsor	Collaborator
National Bureau of Economic Research, Inc.	Geisinger Clinic, Massachusetts Institute of Technology, National Institute on Aging (NIA)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Flu Vaccination (Among Subject Cohabitants) Within 28 Days	Cohabitant of study subject received flu vaccination	Within 28 days of when the study subject is randomized
Other	Flu Vaccination at Appointment by Gender	Received flu vaccination at relevant PCP or specialty appointment.	3 days after the patient is randomized.
Other	Flu Vaccination at Appointment by Race	Received flu vaccination at relevant PCP or specialty appointment.	3 days after the patient is randomized.
Other	Flu Vaccination at Appointment by Ethnicity	Received flu vaccination at relevant PCP or specialty appointment.	3 days after the patient is randomized.
Primary	Flu Vaccination at Appointment	Received flu vaccination at relevant PCP or specialty appointment.	3 days after patient is randomized
Secondary	Flu Vaccination Within 7 Days	Received flu vaccination	Within 7 days of when patient is randomized
Secondary	Flu Diagnosis	Received a "high confidence flu" diagnosis (with positive polymerase chain reaction [PCR]/antigen/molecular test) and/or "likely flu" diagnosis (as assessed via International Classification of Disease [ICD] codes or Tamiflu administration or positive PCR/antigen/molecular test); Note that "likely flu" is a superset of the "high confidence flu" diagnoses.	During the 2021-22 flu season (Up to 8 months, from the time the patient is randomized through April 30, 2022)
Secondary	Flu Complications	Diagnosed with flu-related complications	During the 2021-22 flu season (Up to 11 months, from the time the patient is randomized through July 31, 2022)