Family background to and personal characteristics underlying teenage smoking. Background to teenage smoking.

Smoking habits at the age of 14 were studied in a series of about 11,000 children in Northern Finland. This cohort study was started before the birth of the child as a family inquiry. 6.4% of the children smoked every day and 59.5% were non-smokers. Of the family background variables, parents' smoking, a one-parent family, and number of children in the family had the strongest association with juvenile smoking. Family background variables explained only 6.5% of the total variance in smoking among the girls and 3.5% among the boys, but when characteristics of the children themselves were also introduced into the analyses, 55.7% and 42.7% of the variance respectively could be explained. Juvenile smoking had the strongest association with drinking and excessive drinking of alcohol, poor school performance, less frequent participation in sports and greater body height.