IQR, interquartile range; HLA, human leukocyte antigen; VAS, visual analog scale; BASDAI, Bath Ankylosing Spondylitis Disease Activity Index; BAS-G, Bath Ankylosing Spondylitis Patient Global Score; ASDAS, Ankylosing Spondylitis Disease Activity Score; NSAID, non-steroidal anti-inflammatory drug; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; csDMARD, conventional synthetic disease-modifying anti-rheumatic drug. Here, CRP is linked to ankylosing spondylitis.