An interventional study of Hybrid chatbot and Rule-based chatbot in Vaccination Promotion, sponsored by Chinese University of Hong Kong. Not yet recruiting. Open to participants aged 65 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-13.
Sponsored by Chinese University of Hong Kong · Not applicable, Interventional, and Health services research
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This study is a partially blinded (outcome assessors and data analysts) and parallel-group randomized controlled trial. Community-dwelling people aged ≥65 years who have not received the SIV for the approaching flu season will be randomized evenly (1:1) into either the intervention group or the control group. During the intervention period, the intervention group will have access to the hybrid combination of a rule-based chatbot (SIV-Chatbot) with the ChatGPT-supported real-time Question \& Answer (QA) functions, while the control group will have access only to the SIV-Chatbot.
The SIV-Chatbot will deliver the same interventions for both groups. The number of intervention sessions (four) and timing (week 0, 2, 4 \& 6) will also be the same. In the intervention group, the hybrid Chatbot will invite the participants to raise open-ended questions related to SIV using flexible methods (such as voice messages, typing with keyboards, or handwriting) at each session. The ChatGPT will answer these questions immediately in the format of text messages. The functions can be used repeatedly throughout the intervention period (weeks 0-6), and participants will be free to spend as much time as they want on such functions.
Telephone interviews will be conducted at baseline (T0), after completion of the intervention (T1), and six months after T1 (T2). The primary outcome will be the self-reported SIV uptake measured at T2. The research team will validate that outcome by requesting the participants upload an image of their SIV receipt, while hiding their personal identification, via the WhatsApp account used in this study.
Chinese University of Hong Kong is the lead sponsor of 1,455 studies on the registry; 475 are open to participants now.
Of its 6 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Have access to the hybrid combination of a rule-based chatbot (SIV-Chatbot) with the ChatGPT-supported real-time QA functions
Behavioral: Hybrid chatbot
Have access only to a rule-based chatbot (SIV-Chatbot)
Behavioral: Rule-based chatbot
After assessing participants' stage of change (SOC) regarding SIV uptake, the rule-based component (SIV-Chatbot) will deliver online interventions tailored to their current SOC. There will be four intervention sessions at week 0, 2, 4 and 6. In addition, the hybrid Chatbot will invite the participants to raise open-ended questions related to SIV using flexible methods at each session. The ChatGPT will answer these questions immediately in the format of text messages. The functions can be used repeatedly throughout the intervention period (weeks 0-6), and participants will be free to spend as much time as they want on such functions.
After assessing participants' stage of change (SOC) regarding SIV uptake, the rule-based chatbot (SIV-Chatbot) will deliver online interventions tailored to their current SOC. There will be four intervention sessions at week 0, 2, 4 and 6.
Uptake of seasonal influenza vaccination
The primary outcome will be the self-reported seasonal influenza vaccination uptake measured at T2 (six months after completion of the intervention). The research team will validate that outcome by requesting the participants upload an image of their receipt.
Time frame: Six months after completion of the intervention
Stage of change related to seasonal influenza vaccination uptake
Participants' SOC will be measured at T0 (baseline), T1 (after completion of intervention), and T2 (six months after completion of the intervention) by using validated questions
Time frame: T0 (baseline), T1 (after completion of intervention), and T2 (six months after completion of the intervention)
Knowledge and attitudes related to seasonal influenza vaccination
Knowledge and attitudes will be measured at T0 (baseline) and T2 (6 months after completion of the intervention) by validated tools
Time frame: T0 (baseline) and T2 (6 months after completion of the intervention)
No study locations are listed for this record.
Plan to share: No — The data presented in this study are available from the corresponding author upon request. The data are not publicly available as they contain sensitive personal information.
No publications or documents are linked to this record.
Start is estimated for Nov 2026; primary completion for Dec 2027, 13 months later.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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