Table 1

The performance of the ASAS recommendations in a primary care CLBP population (N=941) calculated per number of SpA parameters present in a patient

Number of parameters present*Sensitivity (%)Specificity (%)PPV (%)
  • *Parameters as described by the ASAS recommendations; inflammatory back pain; HLA-B27 positivity; sacroiliitis on imaging (X-ray or MRI); peripheral manifestations (arthritis, enthesitis, dactylitis); extra-articular manifestation (psoriasis, inflammatory bowel disease, uveitis); positive family history for SpA; good response to non-steroidal anti-inflammatory drugs; elevated acute phase reactants (ESR or CRP).

  • ASAS, Assessment of SpondyloArthritis international Society; CLBP, chronic low back pain; CRP, C reactive protein; ESR, erythrocyte sedimentation rate; SpA, spondyloarthritis; PPV, positive predictive value.