Psychological mechanisms of behavioral change: Trajectories of self-efficacy and motivation among Tunisian health science students using a mobile application to quit smoking - A prospective observational study.

Tobacco use remains a leading preventable cause of morbidity and mortality worldwide, with high prevalence among Tunisian health sciences students. Psychological determinants such as motivation and self-efficacy are key predictors of smoking cessation success. Mobile health (mHealth) interventions offer scalable support, yet their influence on these psychological mechanisms is underexplored in specific contexts. This study aimed to evaluate changes in motivation and self-efficacy to quit smoking among health sciences students using a culturally adapted mobile app in Tunisian dialect, and to examine associations with smoking behavior. A prospective observational study was conducted in 2023 involving 192 daily smoking first-year health sciences students in Sousse, Tunisia. Participants used the app for one month and completed baseline and follow-up assessments of motivation (Q-MAT) and smoking self-efficacy scales, nicotine dependence and smoking behavior were recorded. Paired t-tests and regression analyses assessed changes and predictors of psychological outcomes. Among 107 participants completing follow-up, motivation scores significantly increased from 5.6 ± 4.23 to 9.7 ± 3.26 (p < 0.001), with a redistribution toward higher motivation levels. Although overall self-efficacy scores remained stable, the proportion of participants with high self-efficacy increased significantly (p < 0.001).. Changes in motivation and self-efficacy were positively correlated (r = 0.76, p = 0.001) and associated with reductions in smoking behavior. The use of a culturally appropriate mobile application increases motivation and self-efficacy to quit smoking among Tunisian health science students, thereby promoting smoking reduction. Mobile interventions targeting these psychological mechanisms can complement traditional cessation strategies. Conventional approaches, including face-to-face counseling, pharmacotherapy, group therapy, and telephone support, are effective but often difficult to implement widely in resource-limited settings. In Tunisia and similar contexts, barriers such as limited access to qualified professionals, high costs, geographical constraints, and stigma may restrict their use. Mobile health interventions therefore represent an accessible and cost-effective complementary solution.