A new national smokefree law increased calls to a national quitline

For 24 months prior to the law, and 12 months after the law, data were collected on: (i) Quitline caller registrations and the issuing of nicotine replacement therapy (NRT) vouchers by the Quitline Service; (ii) expenditure on Quitline-related television advertising; (iii) expenditure on other smokefree television advertising; and (iv) print media coverage of smoking in major New Zealand newspapers. These data were inputs to a time series analysis using a Box-Jenkins transfer function model. This used the law change as the intervention variable, with the response series being the monthly Quitline caller rates and monthly first time NRT voucher issue rates.The monthly rates of Quitline caller registrations and NRT voucher issues were observed to increase in the months after the law change. The increase in both these outcomes was even greater when considered in terms of per level of Quitline advertising expenditure (though these patterns may have partly reflected marked reductions in advertising expenditure at the time of the law change and hence are of limited validity).In the more robust time series analyses, the law change (intervention variable) had a significant effect (p = 0.025) on increasing the monthly caller registration rate in December 2004. This was after adjusting for the possible effects of Quitline advertising expenditure, print media coverage, and other smoking-related advertising expenditure.The new national smokefree law resulted in increased quitting-related behaviour. This would suggest there is an extra opportunity for health agencies to promote quitting at such times.The Smoke-free Environments Act passed in New Zealand in 1990 made many indoor workplaces smokefree, including: shops, most offices and some other workplaces (along with partial restrictions on smoking in cafés and restaurants). In December 2004, nearly all the provisions of the new Smokefree Environments Amendment Act of 2003 became operational. This Act had the effect of making al