The transtheoretical model (TTM) is an integrated model that recognizes various degrees of motivation to change.7,8 The TTM postulates specific factors and mechanisms associated with accelerating changes by individuals. The integrated TTM offers a series of determinants of change, including a set of psychological constructs: stages of change, experiential and behavioural processes of change, pros and cons of decisional balance and self-efficacy.9 TTM defines behaviour change as a progressive process through a series of five stages: precontemplation (unawareness of problem, not considering change), contemplation (considering change), preparation (intending to change), action (taking initial steps) and maintenance (sustaining the new behaviour).9,10 Various TTM-based programmes have been effectively designed to change behaviour or to evaluate behavioural changes, including programmes supporting smoking cessation