Table 1

Description of sample and comparison of baseline- and follow-up-sample.


Baseline
Follow-up

Responders, n (%)
9,600 (84%)
6,554 (57% of the original sample, 68% of the baseline sample)
Age at baseline, mean (range)
17.27 (11–22)
17.38 (11–22)
Female/male, n (%)
4,946 (52%)/4,654 (48%)
3,682 (56%)/2,868 (44%)
LBP-long 1994 (LBP>30 days past year), n (%)
588 (6%)
401 (6%)
LBP-all 1994 (LBP>0 days past year), n (%)
3,223 (34%)
2,322 (35%)
Number of days with LBP 1994, mean (SD)
10.46 (38.37)
10.80 (38.78)
Headache-long
591 (7%)
414 (7%)
Headache-all
8.266 (86%)
5.635 (86%)
Asthma
2.685 (28%)
1.785 (27%)
Atopic disease
998 (10%)
707 (11%)

Hestbaek et al. BMC Musculoskeletal Disorders 2006 7:29   doi:10.1186/1471-2474-7-29