Cigarette smoking in a cohort of Sydney schoolchildren: 1971--1974

Cigarette smoking habits of a cohort of Sydney schoolchildren aged 12--13 years in 1971 have been recorded for four years. Smoking prevalence increases steadily over those years, 2.3% of boys and 0.5% of girls smoking 20 or more cigarettes a week at age 12.7 years in 1971, rising to 23.6% of boys and 17.6% of girls by age 15.6 years in 1974. A substantial increase in smoking prevalence in children aged 15.6 years was found in 1974 compared with a similarly aged group studied by the National Health and Medical Research Council (Australia) Subcommittee on Smoking in 1968. Quite a few children changed their smoking habits during the study. Children who changed or left schools smoked more than children who remained at the one school. Attacks of asthma or bronchitis were not related to smoking except that girls who were very heavy smokers reported more of these illnesses in 1974. No changes in lung function could be attributed to smoking by age 14.6 years. New approaches to smoking need to be evaluated in view of its rising prevalence, especially among older schoolchildren.