Smoking Cessation
Conditions
Keywords
Smoking cessation, Behavioral counselling, Digital health, Artificial intelligence, Chatbot, Engagement, Push notification
Brief summary
The goal of this study is to learn whether the timing of weekly chatbot reminders affects user engagement with the chatbot cessation service. Participants enrolled in the routine chatbot cessation service will be included in a micro-randomized trial. The delivery timing of weekly reminders will be randomly assigned across different day types and times of day during the 12-week chatbot cessation service period. The study will use routine chatbot system records to evaluate engagement after reminder delivery, including whether participants respond to the chatbot and how quickly they re-engage with the service.
Detailed description
Sustained user engagement remains a challenge in digital smoking cessation interventions. In this chatbot cessation service, routine weekly AI-generated reminders are used to encourage users to re-engage with chatbot-based smoking cessation support during the 12-week service period. However, the optimal timing for delivering these reminders remains uncertain. This study is an embedded micro-randomized trial conducted within the existing chatbot cessation service. The aim of this study is to evaluate whether the timing of weekly chatbot reminders influences short-term user engagement and to identify optimal reminder delivery schedules. Participants enrolled in the routine chatbot cessation service will be included in the micro-randomized trial through an opt-out approach. The trial will not introduce any additional intervention components, measurements, or study visits beyond the existing chatbot cessation service and follow-up assessments. Participation in the micro-randomized trial will only affect the timing of routine weekly reminders. During the 12-week chatbot cessation service period, excluding the initial welcoming message, the delivery timing of 11 weekly reminders will be randomized across predefined day-type and time-of-day conditions. Reminder strategy will remain unchanged. The primary proximal outcome is meaningful engagement with the chatbot within 24 hours after reminder delivery, as recorded by the chatbot system. Secondary outcomes include reply status, response latency, and meaningful engagement within 48 and 72 hours after reminder delivery. Meaningful engagement is defined as user messages relevant to smoking cessaation. The findings from this study will provide evidence to optimize the timing of routine chatbot reminders and inform future development of optimized reminder strategies and adaptive digital smoking cessation interventions.
Interventions
BEHAVIORALChatbot Cessation Service With Randomized Reminder Timing
The chatbot cessation service provides digital smoking cessation support through a chatbot platform. Participants receive routine chatbot-based cessation support, including scheduled weekly AI-generated reminders during the 12-week service period. Excluding the initial welcoming message, the timing of the remaining 11 weekly reminders will be repeatedly randomized at weekly decision points across predefined day-type and time-of-day conditions. The randomized component is limited to reminder delivery timing. All participants receive the same chatbot content and support.
Sponsors
The University of Hong Kong
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
NONE
Intervention model description
An embedded micro-randomized trial within the chatbot cessation service. Participants will remain in a single chatbot cessation service cohort and will be repeatedly randomized at each weekly decision point to receive scheduled reminders delivered under predefined day-type (weekday/weekend) and time-of-day (morning/afternoon/evening) conditions during the 12-week chatbot cessation service period.
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Able to communicate in Chinese (Cantonese) * Have access to or are willing to use WhatsApp to access the chatbot cessation service * Used any tobacco in the past 30 days (including all types of tobacco products such as cigarette, shisha, electronic cigarettes, and heat-not-burn (HNB))
Exclusion criteria
* Have communication difficulties (either physical or cognitive) that prevent completion of the counselling and assessments * Having queries irrelevant to tobacco control
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Meaningful engagement with chatbot within 24 hours after reminder delivery | Within 24 hours after each randomized reminder delivery during the 12-week chatbot cessation service period | Meaningful engagement is defined as any reply regarding smoking cessation excluding emoji and simple message like "Hi" within 24 hours after receiving a randomized weekly reminder. Engagement will be automatically recorded by the chatbot system. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Any chatbot reply within 24 hours after reminder delivery | Within 24 hours after each randomized reminder delivery during the 12-week chatbot cessation service period | Whether participants provide any reply to the chatbot after receiving a randomized weekly reminder, as recorded by the chatbot system. |
| Response latency after reminder delivery | Within 72 hours after each randomized reminder delivery during the 12-week chatbot cessation service period | The time interval between randomized reminder delivery and the participant's first reply to the chatbot within 72 hours after reminder delivery, as recorded by the chatbot system. |
| Extended meaningful engagement with chatbot after reminder delivery | Within 48 and 72 hours after each randomized reminder delivery during the 12-week chatbot cessation service period | Meaningful engagement is defined as any reply regarding smoking cessation excluding emoji and simple message like "Hi" within 48 and 72 hours after receiving a randomized weekly reminder. Engagement will be automatically recorded by the chatbot system. |
Countries
Hong Kong
Contacts
CONTACTMan Ping Wang
Outcome results
None listed