The influence of best friends and siblings on adolescent smoking: A longitudinal study

The present study investigated whether best friend and/or siblings' smoking affected adolescent smoking. Data of the Dutch Family and Health study was used in which 428 families participated with two adolescent children between the age of 13 and 17 years. Our findings showed that adolescents with older siblings who smoked were more likely to smoke one year later. In contrast, older adolescents were not affected by smoking of their younger siblings. Smoking of the best friend influenced smoking of the younger sibling. With regard to the specific transition from never smoking to smoking initiation, older and younger siblings with a smoking best friend were more likely to start smoking one year later. Younger siblings with older siblings who smoked were more likely to initiate smoking one year later. The influence of friends and siblings on adolescent smoking appeared to be small to moderate.