Blood soluble receptor for advanced glycation end products (sRAGE) levels of rheumatoid arthritis patients stratified with respect to seropositivity and erosivity in comparison with healthy controls. Box plots show the 25th and 75th percentiles. Horizontal lines in bold within boxes indicate medians, and dashed lines indicate means. Vertical bars indicate the 5th and 95th percentiles. Statistical differences with respect to sRAGE levels between groups were calculated using the Mann–Whitney U test. The mean ± standard deviation (median) values are shown. * P < 0.01 as compared with healthy controls. RF, rheumatoid factor; no eros, no erosion.