The "Quit-for-Kids" Project: to Increase Abstinence and Protect Children From Tobacco Smoke Exposure

Background: Around 40% of children worldwide were exposed to secondhand smoke (SHS). Despite reaching a single-digit smoking prevalence of 9.5% in 2022, about one in three children in Hong Kong (36.2%) are still exposed to SHS, mostly at home. Especially children from deprived households, suffer from a higher risk of more pervasive SHS exposure. Aim: The project aims to apply evidence-based interventions to increase smoking cessation and reduce SHS exposure in children of disadvantaged families. The specific objectives of the study are (1) to evaluate the effectiveness of a novel, family-based intervention model in increasing smoking cessation and reducing SHS exposure in children of disadvantaged families, (2) to alert parents in recognizing their child's exposure level and take actions in protecting their child from exposure, (3) to advocate for the adoption of this resource-efficient intervention model in Non-Governmental Organizations(NGOs), District Health Centre Express(DHC/Es), and other smoking cessation service providers in Hong Kong.

Methods: A family-based smoking cessation that collect comprehensive biochemical and environmental data of SHS exposure, and apply evidence-based interventions to prevent the SHS exposure and support quitting in deprived households. Two domains of outcome will be assessed: (1) Effectiveness and overall impact of smoking cessation intervention. (2) Cost-effectiveness analysis and qualitative interviews to estimate the scalability and mechanisms of interventions.

Procedure: Participants will be actively recruited through different channels including direct referral from Non-Governmental Organizations (NGOs) with social housing schemes, referral and recruitment from District Health Centre (DHC), community-based recruitment activities in smoking hotspots, and online advertisement on search engines and social media sites. The eligibility of smokers and non-smokers will be assessed by counselors and invited to join the randomized controlled trial and allocated to one of the groups of the smoking cessation intervention. 6 follow ups at 1 week, 1,2,3,6,12 months will be conducted to both smokers and non-smokers to reveal their SHS exposure level and smoker's quitting progress.

Hypothesis: We hypothesize that the assessment-guided intervention will lead to significant increases in rates of smoking cessation in the intervention group than the control group. Another hypothesis to be investigated is that designated intervention messages are effective to reduce the level of SHS participants and their family members exposed to.

Inclusion criteria

• Hong Kong residents aged 18 or above
• Smoke at least 1 tobacco stick (includes HTP) per day or use e-cigarette daily in the preceding 3-month and verified by exhaled carbon monoxide level of 4ppm (parts per million) or above, assessed by a validated Carbon monoxide Smokerlyzer®
• Living with at least one child of primary 6 or below (aged 12 or below)
• Living with at least one non-smoking family member
• Living in deprived households (monthly household income of less than the median of household monthly income in Hong Kong, HK$ 28,000, or living in subdivided flats or social housing)
• Able to communicate in Chinese (including reading Chinese in IM)
• Able to use the instant messaging tool (e.g., WhatsApp, WeChat) for communication

Exclusion criteria

• Those who have communication barriers (either physically or cognitively)
• Those who are currently participating in other smoking cessation programmes or services