An interventional study of typology-based intervention and Routine Treatment in Smoking (Tobacco) Addiction, Young Adult and RCT, sponsored by The University of Hong Kong. Not yet recruiting at 1 site in Hong Kong. Open to participants aged Up to 25 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-02.
Sponsored by The University of Hong Kong · Not applicable, Interventional, and Prevention
This study aims to develop a typology-based intervention delivered by smoking cessation (SC) counsellors to prevent smoking relapse in ex-smokers who recently quit. The two main research questions include (1) Can a typology-based smoking relapse prevention intervention be feasible and accepted by the smokers and SC counsellors who deliver the new intervention? (2) What is the preliminary evidence on the efficacy of the typology-based smoking relapse prevention to increase tobacco abstinence in ex-smokers who have recently quit? If the intervention shows at least a small effect size (i.e. risk ratio>1.3), or the intervention is feasible while modifications can potentially increase the efficacy, a future definitive RCT is warranted.
Phase 1 Q-method outcomes The outcomes of Phase 1 of this study will be Q-sorts completed by participants which will be inter-correlated producing a matrix for factor rotation and automatic flagging, and the z-score and the factor of the Q-sorts will be calculated.
The tobacco epidemic remains a pressing global health challenge, with tobacco-related illness contributing significantly to a high death rate worldwide. Smoking is the predominant mode of tobacco consumption worldwide and serves as the driving force behind this epidemic. According to the World Health Organization, there are an estimated 1.3 billion tobacco users worldwide currently. In Hong Kong, the smoking rate is estimated to be around 9.5%, with approximately 580 000 daily smokers in 2021. Despite the rate has decreased significantly from 23.3% in 1982, the Hong Kong government aims to further reduce the prevalence from 9.5% to 7.8% in 2025. The high prevalence of smoking imposes a significant public health burden worldwide, with tobacco use killing up to 50% of its users. Additionally, smoking causes cancers, stroke, cardiovascular diseases and respiratory diseases, with around 7000 deaths reported each year. One approach to reduce the smoking prevalence is to promote smoking cessation (SC) treatment among current smokers.
Young smokers constitute a large cohort of new smokers every year. It is estimated that up to 90% of daily smokers first tried smoking before 18 years old. Published studies consistently highlight the concerning prevalence of youth smoking within Hong Kong's community. Data from the recent school survey highlighted that despite only 1.2% of secondary school engages in smoking, a significant portion (7.4%, equivalent to around 24 000 students) of the youth population have previously engaged in smoking behaviour. The rate of youth ever smokers remain high at 7.4% in Hong Kong, equivalent to approximately 24 000 secondary school students, suggesting that youths are eagerly experimenting. This is also evident in the high prevalence of youths trying other tobacco products such as e-cigarettes or heated tobacco products, from 57.4% (178/310) in 2017 to 2018 to 85.9% (243/283) in 2019 to 2020. The shift from occasional smoking to dependency in youth is a crucial stage, making the adolescent years a key period for understanding and addressing smoking behaviours. It represents a key window for targeted interventions to prevent the progression towards regular smoking habits.
Smoking imposes severe health risks and long-term consequences. Effects of tobacco are well demonstrated including the effects of nicotine on brain development. The prevalence of tobacco use among youths not only jeopardizes their immediate health but negatively impacts their future well-being. Moreover, observations from Hong Kong further emphasize the pressing need for effective SC initiatives tailored to the unique needs of youths. The multifaceted challenges such as peer pressure and social influences are faced by struggling youths.
In response to these identified needs, it is imperative to develop comprehensive youth-orientated SC programs that encompass various aspects of prevention, intervention and support. Evidence-based strategies such as counselling services have shown promising outcomes in promoting smoke-free lifestyles among youths. Additionally, collaborations among healthcare institutions, government agencies and community organizations are crucial for maximizing the reach and effectiveness of cessation efforts. By addressing the health needs of local community through targeted youth SC initiatives, the investigators can significantly mitigate the adverse health effects of tobacco use among Hong Kong's young population.
Phase 3 Randomized control trial outcomes The primary outcomes of Phase 3 of this study will be smokers' (1) self-reported abstinence in the past 30 days at 2-month follow-up; (2) iScreen OFD Cotinine Saliva Test Kit (\<30ng/ml) biochemical validated tobacco abstinence; (3) the difference of the feasibility and acceptability score of the typology-based intervention between the intervention and control group.
1,509 studies on the registry are indexed under Smoking; 193 are open to participants now.
This study's planned enrollment of 100 is below the median of 115 across 1,164 interventional studies indexed under Smoking.
Browse Smoking studies →The University of Hong Kong is the lead sponsor of 1,292 studies on the registry; 348 are open to participants now.
Of its 9 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
Inclusion Criteria (Phase 1):
Inclusion Criteria (Phase 3):
Exclusion Criteria (Phase 1 \& 3):
Inclusion Criteria (Phase 2) (for SC counsellors) :
In the Typology-based intervention group, in addition to routine counselling, counsellors will apply typological counselling protocol for the participants. The counselling protocol includes 12 distinguishing statement in Q-methodology. Counsellor will discuss these statements with participants and collect their viewpoints on these statements. After the counselling session, participant can chat with the AI chatbot in WhatsApp for 30 days. The chatbot is specially designed and able to read the content of typological counselling of each participant and provide instant response. In addition to incoming message, the AI chatbot will sent personalized e-messages automatically to encourage participants to engage in discussion with chatbot. The frequency of messages will be one message per week, total 4 for 4 weeks.
Behavioral: typology-based intervention
In the Routine Treatment group, the routine smoking cessation counselling, including generic advice on preventing smoking relapse, will be retained.
Behavioral: Routine Treatment
The typology-based intervention includes: (1) a typology-based counselling, (2) instant response from a specially designed AI Chatbot for 30 days (3) Chatbot initiated AI message for 4 weeks (one message per week). All interventions and materials are delivered by smoking counselling.
The routine smoking cessation intervention includes: (1) Routine counselling generic advice on preventing smoking relapse
self-reported abstinence in the past 30 days at 2-month follow-up
Time frame: 2 mouths
iScreen OFD Cotinine Saliva Test Kit (<30ng/ml) biochemical validated tobacco abstinence
Participants who report tobacco abstinence will be invited for a biochemical validation to test if his/her saliva cotinine is less than 30ng/ml measured by the iScreen OFD Cotinine Saliva Test Kit.
Time frame: 2 months
the difference of the feasibility and acceptability score of the typology-based intervention between the intervention and control group.
The investigators will have 4 feasibility questions and 4 appropriateness questions for counsellor to answer from 1 (Completely disagree) to 5 (Completely agree). Also, the investigators will have 4 acceptability questions for ex-smokers to answer. The investigators would like to observe if there is a difference between the intervention group and the control group
Time frame: 2 months
Time required for the counselling
The average time required for the typological counselling in minutes
Time frame: End of all follow-up (approximately 6 month)
Compliance rate of the SC counsellors in following the intervention protocol
There were 26 questions in the counselling protocol. SC counsellors have to record the number of questions asked during the typological counselling. The rate is calculated by "number of questions asked"/26
Time frame: End of all follow-up (approximately 6 month)
Proportion of screened clients who participate in the RCT
The proportion is calculated by "Number of enrolled participants" / "Total number of participant screened"
Time frame: End of all follow-up (approximately 6 month)
Dropout rate of the participants who consent to the RCT
The dropout rate is calculated by "Number of participants dropout from study" / "Total number of enrolled participant"
Time frame: End of all follow-up (approximately 6 month)
Satisfaction on the SC counsellors
Satisfaction on the SC counsellors is measured by a 5 point Likert scale reported by the enrolled participants, from 1: Very Dissatisfied to 5: Very Satisfied.
Time frame: 2 months
Satisfaction on the AI chatbot and the chatbot initiated e-messages
Satisfaction on AI chatbot and the chatbot initiated is measured by a 10 point Likert scale reported by the enrolled participants, from 1: Very Dissatisfied to 10: Very Satisfied.
Time frame: 2 months
Frequency of reading the chatbot initiated e-messages
The Frequency of reading the e-messages is measured by 5 point Likert scale, that indicate the number of e-messages that the participant had read, from 1 (indicate the participant had read none of the e-messages), to 5 (indicate the participant had read all of the e-messages).
Time frame: 2 months
Perceived effectiveness on the intervention
The perceived effectiveness on the intervention is measured by a 10 point likert scale. Participant will rate the usefulness of the intervention received in helping them to maintain smoking abstinence (10: Very useful \| 0: Useless).
Time frame: 2 months
Satisfaction on the enrolment procedures
Satisfaction on the enrolment procedures is measured by a 10 point Likert scale reported by the participants (0: The enrollment procedure is slow and complicated \| 10: the enrollment procedure is fast and simple).
Time frame: 2 months
Intention to recommend the intervention to other smokers
Intention to recommend the intervention to other smokers is measured by a 10 point Likert scale, 10: strongly recommended to other smokers \| 0: not recommended to other smoker
Time frame: 2 months
Satisfaction about the intervention from SC counsellor
Satisfaction about the intervention from SC counsellor is measured by a 5 point Likert scale. SC counsellor will rate the effectiveness of the typological counselling in helping their client to quit smoking, from 1: very ineffective to 5: very effective.
Time frame: End of all follow-up (approximately 6 month)
Perceived appropriateness of the intervention length from SC counsellor
The perceived appropriateness of the intervention length from SC counsellor is measured by a 5 point Likert scale. SC counsellor will be asked if they agreed that the length of the typological counselling is suitable for their client, from 1 strongly disagree to 5 strongly agree.
Time frame: End of all follow-up (approximately 6 month)
Satisfaction on the enrolment and counselling procedures from SC counsellors
The satisfaction on the enrolment procedures from SC counsellors is measured by a 5 point Likert scale. Counsellors will be asked if they agreed that enrolment and counselling procedures is simple and could be easily done in the SC clinics, from 1: strongly disagree to 5: strongly agree.
Time frame: End of all follow-up (approximately 6 month)
Perceived effectiveness of the counselling protocol from SC counsellor
The perceived effectiveness of the counselling protocol from SC counsellor is measured by a 5 point Likert scale. SC counsellor will be asked if they agreed that the typological intervention can help them screen out smokers who are prone to relapse, from 1: strongly disagree to 5: strongly agree.
Time frame: End of all follow-up (approximately 6 month)
Perceived clients' acceptance of the intervention from SC counsellor
The Perceived clients' acceptance of the intervention from SC counsellor is measured by a 5 point Likert scale. Participants are asked if they agreed that counselling content provided the SC counselling gain their trust and acceptance, from 1: strongly disagree to 5: strongly agree.
Time frame: 2 months
Intention to apply this intervention in other clients from SC counsellors
Intention to apply this intervention in other clients from SC counsellors is measured by a 5 point Likert scale. SC counsellors are asked if they want to apply the typological intervention to other clients in future, from 1: SC counsellors will not apply it to their client in the future, to 5: SC counsellors want to apply it their client in the future.
Time frame: End of all follow-up (approximately 6 month)
Plan to share: Yes — Research data and documentation will be available upon request
Supporting information: Study protocol, Statistical analysis plan, Informed consent form, Clinical study report, Analytic code
Time frame: 3 years after the completion of the relevant publications
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