Figure 2

Percentage of patients with positive immune response defined as at least two-fold increase in prevaccination antibody levels for serotype 6B, 23F and both 6B and 23F in different treatment groups. Statistically significant differences in positive immune response for both 23F and 6B serotypes when two different treatment groups were compared to each other (Chi-squared test) are indicated. MTX, methotrexate; SpA, spondyloarthritis; NSAID, non-steroidal anti-inflammatory drug.