Table 1.
Background characteristics
| CFS patients | Healthy controls | P value | |
|---|---|---|---|
| Count—no. | 120 | 68 | |
| Gender—no. (%) | |||
| Male | 32 (27) | 22 (32) | 0.408 |
| Female | 88 (73) | 46 (68) | |
| Ethnicity—no. (%) | |||
| Scandinavian | 118 (98) | 62 (91) | 0.027 |
| Not Scandinavian | 2 (1.7) | 6 (8.8) | |
| Age—years, mean (SD) | 15.4 (1.6) | 15.1 (1.6) | 0.179 |
| Body mass index—kg/m2, mean (SD) | 21.5 (4.2) | 20.6 (3.7) | 0.131 |
| Experienced menarche (females only)—no. (%) | |||
| No | 11 (13) | 5 (19) | 0.411 |
| Yes | 75 (87) | 21 (81) | |
| Days since last menstrual bleeding (females only)—median (IQR) | 15 (15) | 16 (14) | 0.884 |
| Disease duration—months, median (IQR) | 18 (14) | n.a. | n.a. |
| Depressive symptom score—mean (SD) | 17 (10) | 6 (8) | <0.001 |
| Fatigue score—mean (SD) | 19 (6) | 9 (5) | <0.001 |
| Steps per day—mean (SD) | 4662 (2386) | 10,293 (3716) | <0.001 |
| Adherence to CDC diagnostic criteria—no. (%) | |||
| No | 29 (25) | n.a. | n.a. |
| Yes | 88 (75) | n.a. | |
| Adherence to Canada diagnostic criteria—no. (%) | |||
| No | 69 (60) | n.a. | n.a. |
| Yes | 46 (40) | n.a. | |
CFS chronic fatigue syndrome, SD standard deviation, IQR interquartile range, n.a. not applicable