Many children have a quick puff on a cigarette from time to time but not all of them go on to get hooked on tobacco. Researchers from Columbia University in New York studied 660 children, all of whom had smoked a cigarette when they were first interviewed in Year 6. The children were then followed up in Year 10 to see whether they had become hooked on tobacco. The researchers found that enjoying a first puff on a cigarette, having parents who smoked, being hooked in Year 6 and smoking more in Year 6 had the strongest effects on adolescent nicotine dependence in Year 10. Perceived peer smoking and teenage behaviour problems were less important factors.
Hu, Mei-Chen ... [et al] - Risk and protective factors for nicotine dependence in adolescence
Journal of Child Psychology and Psychiatry doi:10.1111/j.1469-7610.2010.02362.x