A RCT Evaluating an Online Intervention in Increasing Pneumococcal Vaccination Among Older Adults

A Randomized Controlled Trial Evaluating a Theory-based Online Intervention Via Fully Automated Chatbot in Increasing Pneumococcal Vaccination Among Community Dwelling Individuals Aged ≥65 Years

Status

UNKNOWN

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT05772117

Enrollment

374

Registered

2023-03-16

Start date

2023-03-13

Completion date

2024-08-31

Last updated

2023-04-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Vaccination Refusal

Brief summary

To evaluate the relative efficacy of an online intervention based on the Trans-theoretical Model delivered by a fully-automated Chatbot with natural language processing functions versus a control in promoting pneumococcal vaccination uptake among Hong Kong people aged ≥65 years. A total of 374 participants will be randomized evenly to either the intervention group or the control group. Participants in the intervention group will receive Chatbot-delivered interventions tailored to their stage of change regarding PV uptake in a conversational way at Month 0, 1, 2, and 3. Participants in the control group will receive Chatbot-delivered general information related to PV at Month 0, 1, 2, and 3. All participants will be followed up 6 and 12 months after completion of the intervention.

Interventions

BEHAVIORALChatbot-delivered interventions tailored to stage of changes

Participants receive Chatbot-delivered interventions tailored to their stage of change regarding PV uptake in a conversational way at Month 0, 1, 2, and 3.

BEHAVIORALChatbot-delivered standard interventions

Participants receive Chatbot-delivered general information related to PV at Month 0, 1, 2, and 3.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

HEALTH_SERVICES_RESEARCH

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

65 Years to No maximum

Healthy volunteers

Inclusion criteria

* aged ≥65 years * having Hong Kong ID * Chinese speaking * have not received any penumococcal vaccination * willing to be followed up by telephone * having a smartphone * able to send and read text/voice messages via smartphone.

Exclusion criteria

* blindness or deafness * not able to communicate with others effectively * with known contradictions of pneumococcal vaccination * having been diagnosed with major psychiatric illness * scored ≤16 in the validated telephone version of the Cantonese Mini-mental State Examination (T-CMMSE).

Design outcomes

Primary

Measure	Time frame	Description
Pneumococcal vaccination uptake	12 months	Self-reported uptake of pneumococcal vaccination within the 12-month follow-up period

Countries

Hong Kong

Contacts

Primary ContactZixin Wang, PhD

wangzx@cuhk.edu.hk+852 22528740

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026