Table 1 Characteristics of the participants: daily pain, age, grade, gender, parental educational level, sleep duration, use of medication, and self-efficacy (n = 12,867)
| Â | Girls | Boys | p-value* |
|---|---|---|---|
Total number of participants, n (%) | 6318 (49) | 6549 (51) | Â |
Daily pain | |||
 Head, n (%) | 659 (11) | 161 (3) | < 0.001 |
 Shoulders/neck, n (%) | 545 (9) | 214 (4) | < 0.001 |
 Joints/muscles, n (%) | 312 (5) | 195 (3) | < 0.001 |
 Stomach, n (%) | 287 (5) | 109 (2) | < 0.001 |
 Any of the above, n (%) | 1126 (19) | 438 (7) | < 0.001 |
Self-efficacy | |||
 Self-efficacy, mean (95% CI) | 60 (59–61) | 70 (70–71) | < 0.001 |
Sleep | |||
 Short sleep duration, weekdays (< 8 h), n (%) | 3104 (59) | 2726 (52) | < 0.001 |
Depression | |||
 Symptoms of depression (> 3), n% | 1275 (21) | 366 (6) | < 0.001 |
Age | |||
 8th grade junior high school (14–15 yrs), n (%) | 1537 (25) | 1523 (24) |  |
 9th grade junior high school (15–16 yrs), n (%) | 1473 (24) | 1562 (25) |  |
 10th grade junior high school (16–17 yrs), n (%) | 1506 (24) | 1637 (26) |  |
 11th grade senior high school (17–18 yrs), n (%) | 1649 (27) | 1628 (26) | 0.137 |
Parental education | |||
 Low paternal education, n (%) | 1888 (34) | 1937 (34) | 0.601 |
 Low maternal education, n (%) | 1661 (29) | 1638 (28) | 0.306 |
Medication use | |||
 High use (more than once a week), n (%) | 1420 (23) | 673 (11) | < 0.001 |