Background characteristics
| Included (n=43) | Eligible, not included (n=48) | ||
| Treatment (n=21) | Control (n=22) | ||
| Sex, n (%) | |||
| Male | 4 (19) | 6 (27) | 14 (29) |
| Female | 17 (81) | 16 (73) | 34 (71) |
| Age, years, mean (SD) | 17.7 (1.4) | 16.9 (1.7) | 17.4 (1.4) |
| BMI, kg/m2, mean (SD) | 22.5 (3.3) | 21.6 (2.3) | 22.1 (2.7) |
| Adheres to Canada 2003-criteria, n (%) | |||
| Yes | 3 (14) | 7 (32) | 9 (19) |
| No | 18 (86) | 15 (68) | 39 (81) |
| Adheres to Fukuda-criteria, n (%) | |||
| Yes | 5 (24) | 11 (50) | 10 (21) |
| No | 16 (76) | 11 (50) | 38 (79) |
| Epstein-Barr virus (EBV) load, copies in blood, n (%) | |||
| Negative (<160) | 9 (43) | 13 (65) | 22 (49) |
| Low (1600–2000) | 7 (33) | 5 (25) | 14 (31) |
| Moderate/high (>2000) | (5 (24) | 2 (10) | 9 (20) |
| EBV-VCA-IgG, titre, median (IQR) | 152 (107) | 181 (212) | 175.5 (198) |
| Blood cytotoxic T cell (CD8+) count, 106 cells/L, mean (SD) | 683 (248) | 648 (232) | 632 (253) |
| Efficacy variables | |||
| Chalder Fatigue Questionnaire, total sum score, mean (SD) | 20.0 (3.3) | 19.4 (2.9) | 19.1 (4.8) |
| Postexertional Malaise, score, mean (SD) | 2.9 (1.5) | 2.8 (1.3) | 2.7 (1.2) |
| Brief Pain Inventory, total sum score, mean (SD) | 10.4 (5.2) | 13.1 (4.5) | 11.5 (5.5) |
| Karolinska Sleep Questionnaire, total sum score, mean (SD) | 53.0 (14.9) | 45.6 (10.7) | 52.0 (13.4) |
| Hospital Anxiety and Depression Scale, total sum score, mean (SD) | 13.1 (5.8) | 16.5 (6.5) | 12.1 (6.2) |
| Paediatric Quality of Life, total average score, mean (SD) | 67 (14) | 62 (15) | 70 (18) |
| Functional Disability Inventory, total sum score, mean (SD) | 12.2 (8.8) | 13.7 (8.3) | 10.1 (10.9) |
| Steps/day, number, mean (SD) | 7998 (4598) | 8376 (3119) | 9255 (3795) |
P values are based on χ2 test, Fisher’s exact test, Student t-test or Mann-Whitney’s test, as appropriate.
BMI, body mass index; VCA, Viral Capsid Antigen.