Predicting students' intention to smoke by theory of planned behaviour variables and parental influences across school grade levels.

Differences were examined in Theory of Planned Behaviour determinants of students' intention to smoke including parents' attitudes towards smoking and parents' current cigarette use among Greek students of different school grade levels. Students (N = 763) aged 10-18 years reported their attitudes towards smoking, subjective norms, perceived behavioural control, self-identity and intention to smoke while their parents (N = 525) reported their attitudes towards smoking and their current cigarette use. All the TPB variables increased from lower to higher school grade level. Multi-sample path analyses showed that parent's attitudes towards smoking positively predicted students' intention to smoke only for elementary school children. Parents' current cigarette use did not contribute significantly. Students' attitudes, perceived behavioural control and self-identity predicted systematically intention to smoke in contrast to the subjective norm that did not contribute at all. Perceived behavioural control contributed to a higher degree in intention to smoke for senior high school students compared to the junior high school and elementary students. Self-identity contributed to a higher degree in intention to smoke for elementary compared to the junior high school students. The results of this study suggests that the determinants of smoking vary between early and late adolescence.