Mobile Chat Messaging for Smoking Relapse Prevention

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Effectiveness of Mobile Chat Messaging for Preventing Relapse in Smokers Who Have Recently Quit Smoking: a Randomised Controlled Trial

Conditions
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Smoking Cessation

Intervention / Treatment
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* Behavioral: Standard smoking cessation treatment
* Behavioral: Personalised chat messaging
* Behavioral: SMS text messaging


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hong Kong residents aged 18 years or above Own a smartphone with WhatsApp installed Enrolled in a smoking cessation program under Tung Wah Group of Hospitals Integrated Centre on Smoking Cessation Smoked daily before the present quit attempt Abstained from smoking for 3 to 30 days Exclusion Criteria: Diagnosed with a mental disease or on regular psychotropic drugs Participating in other ongoing smoking cessation studies

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Mobile chat messaging<br>Standard smoking cessation treatment + Personalised chat messaging | Behavioral: Standard smoking cessation treatment<br>* Standard smoking cessation treatment (behavioural and pharmacotherapy) provided by Tung Wah Group of Hospitals Integrated Centre on Smoking Cessation<br>Behavioral: Personalised chat messaging<br>* 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).<br>|
| Active Comparator: SMS messaging<br>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<br>* Standard smoking cessation treatment (behavioural and pharmacotherapy) provided by Tung Wah Group of Hospitals Integrated Centre on Smoking Cessation<br>Behavioral: SMS text messaging<br>* SMS text messaging on generic information about the harms of smoking and the benefits of quitting for 3 months from randomisation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Biochemically validated tobacco abstinence | Verified by an exhaled carbon monoxide level of lower than 5 parts per million or a negative salivary cotinine test | 6 months after randomisation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Self-reported 6-month prolonged tobacco abstinence | Not more than five lapses permitted for 6 months after baseline | 6 months after randomisation | 
| Self-reported 7-day point prevalent tobacco abstinence | Being completely smoke-free in the past 7 days | 3 months after randomisation | 
| Self-reported 7-day point prevalent tobacco abstinence | Being completely smoke-free in the past 7 days | 6 months after randomisation | 
| Self-reported relapse rate | Defined as use of tobacco products for 7 consecutive days or longer | 3 months after randomisation | 
| Self-reported relapse rate | Defined as use of tobacco products for 7 consecutive days or longer | 6 months after randomisation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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relapse prevention, recurrence, mHealth, instant messaging, WhatsApp, chatbot, conversational agent, Chinese