Daily and weekly smoking prevalence (95% confidence intervals) in groups defined by: (1) strength of school smoking policy; (2) enforcement of pupil smoking policy; and (3) enforcement of teacher smoking policy
| Daily smoking (%) | Weekly smoking (%) | |
| (1) School no smoking policy | ||
| Strong (9 schools, 205 pupils) | 9.5 (6.1 to 12.9) | 17.1 (14.1 to 20.0) |
| Medium (39 schools, 993 pupils) | 21.0 (17.8 to 24.2) | 25.5 (21.7 to 29.2) |
| Weak (7 schools, 177 pupils) | 30.1 (23.6 to 36.6) | 34.7 (24.7 to 44.7) |
| (2) Pupil enforcement | ||
| High (29 schools, 730 pupils) | 17.7 (13.4 to 22.0) | 22.7 (18.3 to 27.0) |
| Low (26 schools, 645 pupils) | 23.7 (20.2 to 27.2) | 28.6 (24.0 to 33.2) |
| (3) Teacher enforcement | ||
| High (39 schools, 997 pupils) | 20.5 (14.9 to 28.2) | 24.0 (16.5 to 31.5) |
| Low (15 schools, 371 pupils) | 21.5 (14.9 to 28.2) | 26.2 (22.6 to 29.8) |