Characteristics of the participants (17/18 with available data)
| Category | Specific characteristics | Comment | Value |
| General data | Men, No (%) | 14 (82) | |
| Age (years), mean (SD) | 51.5 (15.5) | ||
| Diagnosis | Disease, No (%) | Axial AS: 10 (59%) | |
| AS with peripheral arthritis: 6 (35%) | |||
| AS and ulcerative colitis: 1 (6%) | |||
| Time since diagnosis (years), mean (SD) | 24.5 (12.6) | ||
| Disease duration since symptom onset (years), mean (SD) | 28.6 (14.6) | ||
| Disease activity | BASDAI, mean (SD) | 3.3 (2.1) | |
| BASFI, mean (SD) | 3.5 (2.0) | ||
| VAS pain, mean (SD) | 3.3 (2.6) | ||
| Pain medication | Overall, No (%) | At least one | 15 (88) |
| NSAIDs, No (%) | Regular | 7 (41) | |
| On demand | 6 (35) | ||
| Analgesics, No (%) | On demand | 3 (18) | |
| Opioids, No (%) | Regular | 2 (12) | |
| Corticosteroids | Oral, No (%) | Regular | 1 (6) |
| On demand | 2 (12) | ||
| DMARDs | Overall, No (%) | 7 (41) | |
| Sulfasalazine, No (%) | 2 (12) | ||
| Methotrexate, No (%) | 1 (6) | ||
| Anti-TNF therapy | 4 (24) | ||
| Surgery | Total hip replacement | 1 (6) | |
| Corrective osteotomy | 1 (6) |
AS, ankylosing spondylitis; BASDAI, Bath AS Disease Activity Index; BASFI, Bath AS Functional Index; DMARDs, disease-modifying antirheumatic drugs; NSAIDs, non-steroidal anti-inflammatory drugs; TNF, tumour necrosis factor; VAS, visual analogue scale.