ACPA	Anti-citrullinated peptides’ antibodies
ASAS	Assessment of SpondyloArthritis International Society
BASDAI	Bath Ankylosing Spondylitis Disease Activity Index
BPI	Brief pain inventory
CIRDs	Chronic inflammatory rheumatic diseases
CRP	C-reactive protein
DAS28	Disease Activity Score in 28 joints
ESR	Erythrocyte sedimentation rate
HAD	Hospital anxiety and depression
HAQ	Health assessment questionnaire
HIT-6	Six-item Headache Impact Test
IHS	International Headache Society
IQR	Interquartile range
NSAID	Non-steroidal anti-inflammatory drug
PCS	Pain catastrophizing scale
PsA	Psoriatic arthritis
RA	Rheumatoid arthritis
RF	Rheumatoid factor
SD	Standard deviation
SpA	Spondyloarthritis
TNF	Tumor necrosis factor
VAS	Visual analogue scale