Table 1.

Patient characteristics according to diagnosis and referral strategy.

GroupAge, yrs, mean ± SDAge of Back Pain Onset, yrs, mean ± SDDuration of Back Pain, yrs, mean ± SDMales %HLA-B27+, %
All patientsStrategy 1 (n = 318)38.1 ± 11.328.7 ± 9.28.3 ± 9.553.155.2
Strategy 2 (n = 242)39.5 ± 10.929.2 ± 8.98.6 ± 9.355.456.1
Ankylosing spondylitisStrategy 1 (n = 82)37.4 ± 11.926.5 ± 8.39.3 ± 10.861.081.7
Strategy 2 (n = 55)38.2 ± 11.928.5 ± 10.19.8 ± 9.969.183.6
Nonradiographic axial SpAStrategy 1 (n = 51)39.4 ± 13.129.4 ± 9.29.1 ± 9.447.174.5
Strategy 2 (n = 34)37.0 ± 11.028.2 ± 7.77.9 ± 9.150.067.7
Possible SpAStrategy 1 (n = 43)35.1 ± 10.727.6 ± 9.26.5 ± 8.958.159.5
Strategy 2 (n = 38)39.5 ± 11.329.4 ± 9.98.4 ± 9.065.859.5
Non-SpAStrategy 1 (n = 142)38.9 ± 10.229.9 ± 9.68.0 ± 8.949.331.7
Strategy 2 (n = 115)40.9 ± 10.131.3 ± 8.38.4 ± 9.247.038.0
  • SpA: spondyloarthritis.