Objective: To investigate trends in smoking and associated demographic factors among fourth form (14-15 years) school students.
Method: In 1991, all 35 secondary schools in Wellington, New Zealand, were invited to participate; 15 took part. Smoking behaviours were assessed biennially by self-report. Trends were examined among 5,834 students, using multilevel regression.
Results: When adjusted for sex, ethnicity and their interaction, the baseline (1991) prevalence of smoking within the past month was 18% (95% CI 10-29) rising to 28% (95% CI 15-46) in 1997. The comparable baseline prevalence of daily smoking was 8% (95% CI 3-21) rising to 15% (95% CI 4-40) in 1997. Smoking was more common among girls than boys and most common among Maori girls, for whom the adjusted odds of current and daily smoking were, respectively, 3.40 times (95% CI 2.56-4.52) and 5.00 times (95% CI 3.64-6.87) those of Europeans. School socio-economic status and sex composition added to the explanatory power of the model for daily smoking, but had negligible effect on the odds ratios for sex and ethnic group.
Conclusions and implications: The suggested rise in the prevalence of smoking has implications for future adult smoking rates and health costs. Under-representation of socio-economically disadvantaged schools may have produced conservative estimates. The increased odds of smoking among girls and Maori confirm the need to develop interventions appropriate for these groups.