Smoking among schoolchildren in metropolitan Manila.

A total of 2000 school children aged 8-20 years from 3 sets of elementary and secondary schools in Metropolitan Manila (Philippines) were surveyed to determine the prevalence of smoking among them and to learn the factors affecting the acquisition of the habit. The students were chosen to represent each of the 3 socioeconomic classes of school children in Metropolitan Manila -- 500 each came from socioeconomic class 1 and socioeconomic class 2 and 1000 came from socioeconomic class 3. Cluster random sampling was used in the selection of study subjects. The necessary information was obtained by self-administered questionnaires. The students ranged in age from 8 years to over 20 years with a mean of 14 years for both males and females. The proportion of boys was the same as girls among the ever-smokers. Their mean age was likely comparable. The same result was noted among the nonsmokers. The mean age of ever-smokers was 15 + or - 1.75 years; the mean age of nonsmokers was 13 + or - 2.11. The age differences were significantly different with ever-smokers being generally older than the nonsmokers. The prevalence of ever-smokers in the class 1 school was 34.4%. The proportion of boy ever-smokers was not significantly different from the girl ever-smokers. In class 2 school the prevalence rate was 23.4% and the proportion of boys and girls was not significantly different. Among class 3 school children boy ever-smokers were significantly more prevalent than girl ever-smokers and the combined prevalence of ever-smokers in this social class was 29.2%. A regular smoker among school children is defined as one who smokes at least 1 cigarette per week. The overall prevalence rate of regular smokers in the 3 schools was 6.6% for both sexes (11.6% for males and 1.7% for females). The proportion of boy ever-smokers was about the same or slightly higher than the girl ever-smokers except among the 15-year-olds where the proportion of girl ever-smokers was much higher than those of boy ever-smokers. The older the boy ever-smoker is the higher the probability of him being a regular smoker. This trend was not observed among the girl ever-smokers and girl regular smokers. The male smokers were most prevalent in class 1 school (14.7%) followed by class 3 (11.0%) and class 2 (9.2%). For the female regular smokers class 1 had a rate of 6.3% and class 3 0.6%. Class 2 school did not have any regular female smokers. The most surprising observation was that the smoking habit of the school children male or female was not influenced at all by either parent but the habit of the girl ever-smoker was affected by the brother.