Fig. 1

Seasonal breakdown of rheumatoid arthritis (RA) disease activity according to DAS28-CRP score in 12,839 patients with RA (a) and in a subgroup of 5255 younger patients (< 65 years) (b) in Ninja2016. The proportions of patients categorized as having remission (DAS28-CRP < 2.3), low disease activity (LDA, 2.3 ≤ DAS28-CRP < 2.7), moderate disease activity (MDA, 2.7 < DAS28-CRP ≤4.1), and high disease activity (HAD, DAS28-CRP ≥4.1) in each season are shown in a stacked bar graph. *p < 0.01, **p < 0.05