Hiding tobacco away in shop cabinets has helped lower school student smoking to its lowest level in two decades, University of Otago researchers say.
The scientists have looked at the effect of the 2012 law change, which removed visible tobacco displays from behind the counter, and smoking by 14- and 15-year-olds.
They say there is strong evidence there has been a significant reduction in both experimental and regular smoking, when accompanied by enforcement measures for selling tobacco to minors.
The tobacco industry has a history of saying that tobacco control measures won't work and predicting disastrous effects, even when the evidence suggests otherwise," said lead researcher Professor Richard Edwards.
"They are currently making such arguments to oppose the introduction of plain packaging. This study shows once again that the industry is not to be trusted, and that implementing rigorous tobacco control measures will help protect children from becoming smokers."
The study results have been published in the international journal Tobacco Control.