Table 1 Baseline characteristics among participants at baseline and follow-up, and those lost to follow-up
Participants at baseline and follow-up | Lost to follow-up | Chi2 | |
|---|---|---|---|
n (%) | n (%) | P | |
Gender | |||
Boys | 292 (45.0) | 187 (60.1) | |
Girls | 357 (55.0) | 124 (39.9) | <0.01 |
Age | |||
12 years old | 154 (23.8) | 57 (18.4) | |
13 years old | 475 (73.5) | 239 (77.3) | |
14 years old | 17 (2.6) | 13 (4.2) | 0.09 |
Country of birth | |||
Born in Sweden | 612 (94.4) | 282 (91.0) | |
Born outside Sweden | 36 (5.6) | 28 (9.0) | 0.04 |
Residence | |||
City/Town | 350 (55.6) | 180 (60.8) | |
Village | 160 (25.4) | 64 (21.6) | |
Rural area | 120 (19.0) | 52 (17.6) | 0.30 |
Parental education | |||
High | 352 (54.7) | 146 (47.9) | |
Low | 292 (45.3) | 159 (52.1) | 0.05 |
Mood in family | |||
Good | 572 (90.1) | 270 (89.1) | |
Not good | 63 (9.9) | 33 (10.9) | 0.65 |
Self-rated health | |||
High | 333 (51.7) | 156 (50.5) | |
Medium | 272 (42.2) | 122 (39.5) | |
Low | 39 (6.1) | 31 (10.0) | 0.08 |
Self-esteem | |||
High | 362 (56.7) | 194 (63.6) | |
Medium | 223 (35.0) | 86 (28.2) | |
Low | 53 (8.3) | 25 (8.2) | 0.10 |
Attitudes towards smoking | |||
Very negative | 554 (86.2) | 252 (81.8) | |
Not very negative | 89 (13.8) | 56 (18.2) | 0.08 |
Physical exercise | |||
High | 480 (77.4) | 226 (75.6) | |
Low | 140 (22.6) | 73 (24.4) | 0.54 |
Binge drinking | |||
No | 595 (93.4) | 274 (91.0) | |
Once or more | 42 (6.6) | 27 (9.0) | 0.19 |
Snus use | |||
No | 588 (91.9) | 260 (86.4) | |
Previous or current use | 52 (8.1) | 41 (13.6) | 0.01 |
Smoking | |||
No | 618 (96.7) | 286 (94.4) | |
Yes | 21 (3.3) | 17 (5.6) | 0.09 |