Chat-based Support for Preventing Smoking Relapse

"Subjects will receive personalised instant messaging support for 12 weeks after baseline, address the five problems that contributed to smoking relapse:~(1) lack of support for cessation, (2) negative mood or depression, (3) strong or prolonged withdrawal symptoms, (4) weight gain, and (5) smoking lapses. Updated information about the negative effect of smoking on risk of COVID-19 infection and prognosis will also be delivered."

Subjects will receive regular SMS on generic smoking cessation for 3 months.

Subjects will receive a standard self-help booklet on smoking relapse prevention.