Table 1 Characteristics of the eight included studies.
Name cohort or author | nr-axSpA n | AS n | Study design | Year of inclusion | Data collection | Maximum disease duration for inclusion, years | Mean symptom duration nr-axSpA, mean years (SD) | Mean symptom duration AS, mean years (SD) |
|---|---|---|---|---|---|---|---|---|
GESPIC | 226 | 236 | Cohort | 2000–2004 | Baseline | AS: <10; nr-axSpA <5 | 2.6 (1.7) | 5.2 (2.3) |
Kiltz | 44 | 56 | Cross-sectional | Unknown | n.a. | No | 9.4 (9.5) | 12.8 (10.7) |
DESIR | 295 | 180 | Cohort | 2007–2010 | Baseline | <3 | 1.5 (0.9) | 1.6 (0.9) |
SCQM | 232 | 838 | Cohort | 2005–2011 | Baseline | No | 5.5 (1.8–13.7)b | 12.7 (6.4–22.7)b |
SPACE | 58 | 23 | Cohort | 2009–2014 | Baseline | <2 | 1.1 (0.6) | 1.3 (0.7) |
Esperanza | 182 | 109 | Cohort | 2008–2011 | Baseline | <2 | 1.0 (1.6) | 1.2 (0.5) |
Wallis | 73 | 639 | Cohort | 2003–2012 | Baseline | No | 12.1 (8.5)a | 17.7 (12.3)a |
ESPAC | 132 | 155 | Cohort | 2009–2014 | Unknown | No | 5.8 (5.5) | 11.7 (7.7) |