Table 2. Prevalence and difference in prevalence of symptoms among ninth grades in Western Sweden, year 2000 and 2008.
| Girls | Boys | |||||||
|---|---|---|---|---|---|---|---|---|
| Crude prevalence, % | PD, 2008–2000, % | Crude prevalence, % | PD, 2008–2000, % | |||||
| (95% CI) | (95% CI) | (95% CI) | (95% CI) | |||||
| 2000 | 2008 | Crude PD | Adjusted PD | 2000 | 2008 | Crude PD | Adjusted PD | |
| N = 4792 | N = 5758 | N = 10550 | N = 10441 | N = 4711 | N = 5616 | N = 10327 | N = 10232 | |
| 62 | 64 | 1 | 1 | 55 | 50 | -5 | -5 | |
| Pain in upper body (ever) | (60.8 ; 63.6) | (62.3 ; 64.8) | (-0.5 ; 3.2) | (-0.2 ; 2.9) | (53.4 ; 56.2) | (48.2 ; 50.8) | (-7.2 ; -3.4) | (-7.0 ; -3.7) |
| 32 | 35 | 3 | 3 | 16 | 15 | -1 | -1 | |
| Headache (often) | (30.9 ; 33.5) | (33.8 ; 36.3) | (1.0 ; 4.6) | (1.6 ; 4.7) | (15.1 ; 17.2) | (14.2 ; 16.1) | (-2.4 ; 0.4) | (-2.0 ; 0.4) |
| 18 | 23 | 5 | 6 | 8 | 10 | 2 | 2 | |
| Abdominal pain (often) | (16.9 ; 19.1) | (22.3 ; 24.5) | (3.8 ; 6.9) | (4.4 ; 7.1) | (7.5 ; 9.1) | (9.6 ; 11.2) | (1.0 ; 3.2) | (1.2 ; 3.1) |
| 73 | 75 | 3 | 3 | 61 | 57 | -3 | -3 | |
| Any of the three pain symptom present | (71.7 ; 74.2) | (74.3 ; 76.6) | (0.9 ; 4.2) | (1.2 ; 4.0) | (59.3 ; 62.1) | (56.0 ; 58.6) | (-5.3 ; -1.5) | (-5.0 ; -1.8) |
| 9 | 11 | 2 | 2 | 3 | 3 | -1 | -1 | |
| All three pain symptoms present | (7.8 ; .4) | (10.0 ; 11.6) | (-6.3 ; 10.7) | (1.5 ; 3.4) | (2.7 ; 3.7) | (2.1 ; 3.0) | (-3.9 ; 2.5) | (-1.2 ; -0.1) |
The adjusted values are according to confounder distribution year 2008. PD = prevalence difference. CI = confidence interval. Adjusted PD is adjusted for parental education and foreign origin.