An interventional study of Standard smoking cessation treatment and Personalised chat messaging in Smoking Cessation, sponsored by The University of Hong Kong. Completed at 2 sites in Hong Kong. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-11-20.
Sponsored by The University of Hong Kong · Not applicable, Interventional, and Treatment
Most smokers return to smoking (relapse) after making a quit attempt, but evidence of effective intervention to prevent relapse is scarce. Taking advantage of recent advances in mobile technologies, this study aims to evaluate the effectiveness of a mobile chat messaging-based relapse prevention intervention in promoting successful quitting in people who recently quit smoking (recent abstainers) using a randomised controlled trial design.
Most smokers who made quit attempts and achieved short-term abstinence return to smoking (relapse) over time, even when aided by effective smoking cessation treatment. Since relapse mostly occurred in the first 4 weeks of abstinence, relapse prevention in the early phase of abstinence could potentially boost long-term abstinence. Several behavioural interventions for smoking relapse prevention have been proposed and tested in RCTs. Yet, a 2019 Cochrane review did not find traditional approaches, including self-help materials, telephone counselling and group therapy, effective in increasing long-term abstinence at 6 months or longer.
The widespread use of mobile devices has provided a highly accessible and scalable means for novel behavioural interventions for smoking cessation. A formative qualitative study in current smokers conducted by the investigators showed that mobile chat messaging is a feasible and acceptable platform for delivering smoking cessation support. A subsequent cluster randomised controlled trial on 1148 smokers found that mobile chat messaging combined with brief intervention was effective in increasing biochemically validated abstinence at 6 months. Nonetheless, whether mobile chat messaging could prevent relapse in recent abstainers has remained untested.
The investigators did a pilot trial to confirm the feasibility and acceptability of mobile chat messaging for relapse prevention in recent abstainers. This study aims to evaluate the effectiveness of mobile chat messaging relapse prevention intervention in promoting abstinence in recent abstainers.
304 studies on the registry are indexed under Smoking Cessation; 139 are open to participants now.
This study's enrollment of 590 is above the median of 154 across 285 interventional studies indexed under Smoking Cessation.
Browse Smoking Cessation studies →The University of Hong Kong is the lead sponsor of 1,262 studies on the registry; 340 are open to participants now.
Of its 8 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Standard smoking cessation treatment + Personalised chat messaging
Behavioral: Standard smoking cessation treatment · Behavioral: Personalised chat messaging
Standard smoking cessation treatment + Regular SMS text messaging generic information about the harms of smoking and the benefits of quitting
Behavioral: Standard smoking cessation treatment · Behavioral: SMS text messaging
Standard smoking cessation treatment (behavioural and pharmacotherapy) provided by Tung Wah Group of Hospitals Integrated Centre on Smoking Cessation
Personalised chat messaging focusing on smoking relapse prevention for 3 months from randomisation. A trained counsellor will interact with a participant individually and provide relapse prevention advice via WhatsApp. The participant can also access a supportive chatbot in WhatsApp, which will provide on-demand smoking relapse prevention support when the counsellor is not available (e.g., during nighttime).
SMS text messaging on generic information about the harms of smoking and the benefits of quitting for 3 months from randomisation.
Biochemically validated tobacco abstinence
Verified by an exhaled carbon monoxide level of lower than 5 parts per million or a negative salivary cotinine test
Time frame: 6 months after randomisation
Self-reported 6-month prolonged tobacco abstinence
Not more than five lapses permitted for 6 months after baseline
Time frame: 6 months after randomisation
Self-reported 7-day point prevalent tobacco abstinence
Being completely smoke-free in the past 7 days
Time frame: 3 months after randomisation
Self-reported 7-day point prevalent tobacco abstinence
Being completely smoke-free in the past 7 days
Time frame: 6 months after randomisation
Self-reported relapse rate
Defined as use of tobacco products for 7 consecutive days or longer
Time frame: 3 months after randomisation
Self-reported relapse rate
Defined as use of tobacco products for 7 consecutive days or longer
Time frame: 6 months after randomisation
Biochemically validated tobacco abstinence
Verified by an exhaled carbon monoxide level of lower than 5 parts per million or a negative salivary cotinine test
Time frame: 12 months after randomisation
Self-reported 12-month prolonged tobacco abstinence
Not more than five lapses permitted for 12 months after baseline
Time frame: 12 months after randomisation
Self-reported 7-day point prevalent tobacco abstinence
Being completely smoke-free in the past 7 days
Time frame: 12 months after randomisation
Self-reported relapse rate
Defined as use of tobacco products for 7 consecutive days or longer
Time frame: 12 months after randomisation
Plan to share: No — Request to obtain IPD can be made to the principal invesitgator on reasonable request
This study is completed, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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The University of Hong Kong