Table 2.
Frequency and the respective percentage within brackets of specific disease factors or triggers narrated by patients from the subgroups S1 (n = 43), S2 (n = 93), and S3, (n = 48) in the participant's questionnaire.
| Narrated disease trigger | Subgroups of ME/CFS patients | Total (%) | ||
|---|---|---|---|---|
| S1 (%) | S2 (%) | S3 (%) | ||
| Glandular Fever; tonsilitis; EBV infection | 1 (2) | 25 (27) | 22 (46) | 48 (21) |
| Respiratory infection; pneumonia | 1 (2) | 6 (6) | 3 (6) | 10 (4) |
| Flu-like infection or illness | 2 (5) | 20 (22) | 4 (8) | 26 (11) |
| Gastrointestinal infection | 0 (0) | 6 (6) | 3 (6) | 9 (4) |
| Tropical infections | 0 (0) | 1 (1) | 2 (4) | 3 (1) |
| Other infections including unspecified viral infections | 2 (5) | 33 (35) | 13 (27) | 51 (22) |
| General stress or anxiety | 6 (14) | 11 (12) | 3 (6) | 20 (9) |
| Stress due to personal events | 9 (21) | 6 (6) | 3 (6) | 18 (8) |
| Stress at work or school | 4 (9) | 5 (5) | 2 (4) | 11 (5) |
| Vaccinations | 0 (0) | 4 (4) | 6 (12) | 10 (4) |
| Chemical exposure | 1 (2) | 6 (6) | 0 (0) | 7 (3) |
| Accidents/Injuries/Surgeries | 7 (16) | 2 (2) | 2 (4) | 11 (5) |
| Pregnancy/Childbirth/Postnatal/ Hysterectomy/Endometriosis | 6 (14) | 0 (0) | 0 (0) | 6 (3) |
| Other | 4 (9) | 6 (6) | 0 (0) | 7 (3) |