Brief Summary

This megastudy is a massive randomized controlled trial. By randomizing participants to 10 different intervention conditions simultaneously, the investigators will be able to compare the effectiveness of different interventions to one another and to a control group (in which individuals will only receive the usual communications from their partner organization) to identify which interventions significantly increase vaccination rates. Pharmacy customers will be randomly assigned to receive one of the interventions designed by team scientists to encourage vaccination or to a control group. The baseline intervention will be based on the top-performing SMS intervention identified in the investigators previous megastudies on encouraging vaccination (Milkman et al., 2021b, 2022). Pharmacy customers will receive SMS messages conveying that a COVID booster vaccine is reserved or waiting for them at the pharmacy. Additional behavioral science messaging strategies will be tested by building off of this baseline intervention.

Trial Health

On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment

2,600,000

participants targeted

Target at P75+ for not_applicable covid19

Timeline

Completed

Started Nov 2022

Shorter than P25 for not_applicable covid19

Geographic Reach

1 country

1 active site

Status

completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

3 months study duration

First Submitted

Initial submission to the registry

November 3, 2022

Completed

Same day until next milestone

Study Start

First participant enrolled

November 3, 2022

Completed

4 days until next milestone

First Posted

Study publicly available on registry

November 7, 2022

Completed

1 month until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 8, 2022

Completed

2 months until next milestone

Study Completion

Last participant's last visit for all outcomes

February 6, 2023

Completed

Last Updated

March 3, 2023

Status Verified

March 1, 2023

Enrollment Period

1 month

First QC Date

November 3, 2022

Last Update Submit

March 1, 2023

Conditions

COVID-19

Keywords

COVID-19 vaccinationbehavioral science interventionsvaccination promotion

Outcome Measures

Primary Outcomes (1)

Patient uptake of the COVID bivalent booster
Whether patients receive a bivalent COVID booster at the pharmacy in question
During the 30 days after receiving the SMS/MMS intervention

Secondary Outcomes (2)

Patient uptake of the COVID bivalent booster
60 days after receiving the SMS/MMS intervention
Patient uptake of the COVID bivalent booster
90 days after receiving the SMS/MMS intervention

Study Arms (11)

Holdout control condition with no message

NO INTERVENTION

Participants will only receive the standard pharmacy messaging.

Control condition with "waiting for you" message

EXPERIMENTAL

This control condition will use the text message that we've found to be the best performing in our last mega-study of vaccine text messages to recommend a COVID vaccination.