When do adolescents become smokers?

Figures & data

Table I.  Study population and response frequency in the different years, from 1994 to 2000.

Year (class)	No. of pupils	No. of responders	Response frequency (%)
1994 (grade 6)	2179	2015	92.5
1995 (grade 7)	2186	2034	93.0
1996 (grade 8)	2188	1985	90.7
1997 (grade 9)	2163	1934	89.4
1998 (form 1/grade 10)	2592	2099	80.9
1999 (form 2/grade 11)	2191	1854	84.6
2000 (form 3/grade 12)	2094	1585	75.6

Figure 1.  Development of smoking habits for girls, from grade 6 to form 3 of upper secondary school. Note: The internal dropout varied between two and four during the seven years.

Figure 2.  Development of smoking habits for boys, from grade 6 to form 3 of upper secondary school. Note: The internal dropout varied between two and 12 during the seven years.

Figure 3.  Development of cigarette consumption for the smoking girls, from grade 6 to form 3 of upper secondary school. Note: The internal dropout varied between two and 12 during the seven years.

Figure 4.  Development of cigarette consumption for the smoking boys, from grade 6 to form 3 of upper secondary school. Note: The internal dropout varied between two and 15 during the seven years