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Nationwide Utilization of Danish Government Electronic Letter System for Increasing InFLUenza Vaccine Uptake (NUDGE-FLU)

T

Tor Biering-Sørensen

Status

Completed

Conditions

Influenza
Behavior and Behavior Mechanisms

Treatments

Behavioral: Behavioral Economic Principles

Study type

Interventional

Funder types

Other
Industry

Identifiers

NCT05542004
FLU00180

Details and patient eligibility

About

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.

Full 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.

Enrollment

964,870 patients

Sex

All

Ages

65+ years old

Volunteers

Accepts Healthy Volunteers

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

Trial design

Primary purpose

Other

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

None (Open label)

964,870 participants in 10 patient groups

Control
No Intervention group
Description:
No letter
Standard Letter
Experimental group
Description:
This group will receive a standard letter on the benefits of influenza vaccination without behavioral economic enhancement
Treatment:
Behavioral: Behavioral Economic Principles
Priming & Hot State Activation - 1 reminder
Experimental group
Description:
The standard letter sent out two times instead of once
Treatment:
Behavioral: Behavioral Economic Principles
Depersonalized Letter
Experimental group
Description:
The standard letter without the recipient's name
Treatment:
Behavioral: Behavioral Economic Principles
Gain-Framing/Context
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles
Loss-Framing/Context
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles
Collective Goal
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles
Active Choice/Implementation Intention Prompt
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles
Cardiovascular Gain Frame
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles
Expert Authority
Experimental group
Description:
Text added to the standard letter employing the specified behavioral economic principle
Treatment:
Behavioral: Behavioral Economic Principles

Trial contacts and locations

1

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Data sourced from clinicaltrials.gov

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