MedPath

Nationwide Utilization of Danish Government Electronic Letter System for Increasing InFLUenza Vaccine Uptake

Not Applicable
Completed
Conditions
Behavior and Behavior Mechanisms
Influenza
Interventions
Behavioral: Behavioral Economic Principles
Registration Number
NCT05542004
Lead Sponsor
Tor Biering-Sørensen
Brief Summary

In randomized clinical trials and observational studies, influenza vaccination has been shown to be effective in reducing influenza-related illness, hospitalizations, cardiovascular events, and mortality in select populations. However, the real-world effectiveness of influenza vaccination is limited by its uptake. This study will investigate investigate whether digital behavioral nudges delivered via the official, mandatory Danish electronic letter system can increase influenza vaccine uptake among eligible influenza vaccination candidates.

Detailed Description

The study is a prospective, randomized, open-label implementation trial. The study population will consist of persons identified as eligible for free-of-charge influenza vaccination in the Danish health system aged 18 years and above. Subjects will be identified through Danish nationwide health registries using codes from the International Classification of Diseases, 10th revision (ICD-10) and the Anatomical Therapeutic Chemical (ATC) classification system. Individuals will be randomized to 1 of 10 arms (1 control arm and 9 intervention arms) with each testing different nudging strategies employing various behavioural economic principles. The interventions will be delivered through the official, mandatory Danish electronic letter system. All subject data will be retrieved from the Danish nationwide registries with the exception of information on intervention allocation. Endpoints will be retrieved at prespecified dates using prespecified search algorithms. The study will be performed in collaboration with the Danish Health Data Authority and Statens Serum Institut.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
964870
Inclusion Criteria
  1. Age >=65 years at January 15, 2023 (eligible for free influenza vaccination in the official Danish vaccination program)
  2. Access to the official, mandatory Danish electronic mailbox system
Exclusion Criteria
  1. Persons living in nursing homes

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Priming & Hot State Activation - 1 reminderBehavioral Economic PrinciplesThe standard letter sent out two times instead of once
Collective GoalBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Standard LetterBehavioral Economic PrinciplesThis group will receive a standard letter on the benefits of influenza vaccination without behavioral economic enhancement
Depersonalized LetterBehavioral Economic PrinciplesThe standard letter without the recipient's name
Gain-Framing/ContextBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Active Choice/Implementation Intention PromptBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Loss-Framing/ContextBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Cardiovascular Gain FrameBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Expert AuthorityBehavioral Economic PrinciplesText added to the standard letter employing the specified behavioral economic principle
Primary Outcome Measures
NameTimeMethod
Number of participants who received an influenza vaccineUp to 3 months
Secondary Outcome Measures
NameTimeMethod
Time from intervention delivery to influenza vaccinationUp to 3 months

Trial Locations

Locations (1)

Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte

🇩🇰

Hellerup, Hovedstaden, Denmark

© Copyright 2025. All Rights Reserved by MedPath