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

Ask about smoking history, Warn about the high risk of smoking, Advise to quit as soon as possible, Refer to the smoking cessation services, and Do it again (if the smokers refuse to set a quit date).

1-week sampling of Nicotine Replacement Therapy (NRT) will be provided to support quit attempt. Full pharmacological treatment (12-week) will be available if needed.

Chat-based mHealth personalized psychosocial and behavioural counselling (smoking cessation and SHS exposure reduction messages will be derived from previously tested interventional studies) using baseline children health and biofeedback data to support quitting throughout the intervention period of 3 months.

A financial incentive (vouchers) of HK$ 500 will be provided for biochemically validated smoking abstinence at 3- and 6-month follow-up. Considering a possibly low engagement rate of the smokers in mHealth-based support (17% in our previous trial, non-engagement mostly due to busy work), additional HK$ 200 will be provided for participants who actively engaged in the mHealth counselling (defined by have discussed quitting process for \>2 times) at 3-month follow-up.

A well-designed self-help booklet will be provided to guide and provide detailed information on smoking cessation. The contents include information about the benefits of quitting, smoking and diseases, methods to quit, how to handle withdrawal symptoms, declaration of quitting, etc.

"In a selected subgroup of 50 families with an additional signed consents, four home visits will be done to: 1. Setup an indoor air quality (IAQ) monitor to collect 24hr air quality data (2 weeks), 2. Collect the monitor for data retrieval, 3. Setup the monitor at 6 months follow-up (2 weeks), 4. Collect the monitor for data retrieval.~Environmental assessment derived intervention, including results interpretation and health advice, will be provided via phone calls for the 50 families within 1 week after the data collection."