Effectiveness of SMS Nudging to Increase Coverage of Influenza Vaccination Among the Elderly

NCT06486766 | Not Yet Recruiting

• 1 other identifier: 30052
• Study Type: interventional
• Target: 1,000,000
• Locations: 0 countries
• Sites: N/A

Brief Summary

The trial will investigate to what extent SMS reminders for influenza vaccination increases coverage of influenza vaccination among elderly from the majority population, and among elderly from immigrant groups with low vaccination coverage

Conditions

Influenza

Keywords

influenza vaccination; adult vaccination; coverage; uptake; behavioral nudging; vaccine hesitancy; undervaccination; migrant health

Outcome Measures

Primary Outcomes (1)

• Influenza vaccination coverage (%)

  The percent uptake of the influenza vaccine in the population of interest

  Three months following the intervention, during the 2025/2026 influenza season

Other Outcomes (1)

• COVID-19 vaccination coverage (%)

  Three months following the intervention, during the 2025/2026 influenza season

Study Arms (3)

Control

NO INTERVENTION

Standard care: Influenza vaccination is generally recommended to all individuals aged 65 or older, but there is no systematic individual invitation/reminding/scheduling for vaccination by SMS or any other mode. The control arm is applicable to all three populations (general population, immigrants born in Poland, immigrants born in Ukraine)

Norwegian SMS

EXPERIMENTAL

Behavioral: Norwegian SMS

Polish/Ukrainian SMS

EXPERIMENTAL

Behavioral: Polish/Ukrainian SMS

Interventions

Norwegian SMS BEHAVIORAL

Individuals receive a SMS in Norwegian language at the start of the influenza season, to remind them they are recommended to get the influenza vaccine. This intervention arm is applicable to all three populations (general population, immigrants born in Poland, immigrants born in Ukraine)

Norwegian SMS

Polish/Ukrainian SMS BEHAVIORAL

Individuals receive an SMS in the official language of their native country (i.e., Polish or Ukrainian) at the start of the influenza season, to remind them they are recommended to get the influenza vaccine. This intervention arm is only applicable to the two immigrant populations (immigrants born in Poland, immigrants born in Ukraine)

Polish/Ukrainian SMS

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)

You may qualify if:

• Aged 65+ (age at the end of 2025, i.e., born 1960 or earlier)
• Resident in Norway and have a valid ID number on 1 September 2025
• Have a registered mobile phone number

You may not qualify if:

• Have received the 2025 influenza vaccine prior to the SMS nudge dispatch date
• Have emigrated or died before SMS nudge dispatch date

Sponsors & Collaborators

• Norwegian Institute of Public Health: lead
• University of Oslo: collaborator
• Finnish Institute for Health and Welfare: collaborator
• University of Turku: collaborator
• University Hospital, Akershus: collaborator

Related Publications (1)

• Hansen BT, Klungsoyr O, Labberton AS, Saaksvuori L, Rydland KM, Odeskaug LE, Wisloff T, Meijerink H. Effectiveness of Text Messaging Nudging to Increase Coverage of Influenza Vaccination Among Older Adults in Norway (InfluSMS Study): Protocol for a Randomized Controlled Trial. JMIR Res Protoc. 2025 Feb 25;14:e63938. doi: 10.2196/63938.

  PMID: 39998878 DERIVED

MeSH Terms

Conditions

Influenza, Human; Vaccination Hesitancy

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Vaccination Refusal; Treatment Refusal; Treatment Adherence and Compliance; Health Behavior; Behavior

Study Officials

• Bo T Hansen, PhD

  Norwegian Institute of Public Health

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Hansen

CONTACT

(+47) 21077000; folkehelseinstituttet@fhi.no

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: The outcome measure of the trial is based solely on routinely collected data and those reporting/registering this information will not be aware of whether a vaccinated individual has received an SMS nudge. Thus, the trial is blinded to the outcomes assessor. Moreover, treatment allocation is randomized and computer-generated, there is no interaction between the InfluSMS project team and study participants, and the InfluSMS researchers work with de-identified data and do not know the identity of any participant in the dataset. Due to the inherent characteristics of the intervention, treatment allocation cannot be blinded for participants.
• Purpose: HEALTH SERVICES RESEARCH
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Model Details: The trial is conducted in three populations of elderly (aged 65 years or older) residing in Norway: (i) the general population; (ii) immigrants born in Poland; (iii) immigrants born in Ukraine. In all three populations, the control arm is standard care, i.e., no individual reminder for influenza vaccination. All populations have an intervention arm that will receive an SMS nudge in the Norwegian language. In addition, the Polish and Ukrainian immigrant populations include a second intervention arm that will receive an SMS nudge in Polish or Ukrainian, respectively.

Study Record Dates

• First Submitted: June 27, 2024
• First Posted: July 5, 2024
• Study Start: October 1, 2025
• Primary Completion: January 1, 2026
• Study Completion (Estimated): July 1, 2026
• Last Updated: August 7, 2024

Record last verified: 2024-06

Data Sharing

• IPD Sharing: Will not share