Table 1.

Clinical indicators of PSA disease manifestation

1	Tender joints	For each of the 78 joints based on the presence or absence of tenderness
2	Swollen joints	For each of the 76 joints based on the presence or absence of swelling
3	Enthesitis	For each of the six LEI entheseal sites based on presence or absence
4	Dactylitis	For each of the 10 fingers and 10 toes based on presence or absence
5	mNAPSI	For each of the 10 fingers defined as clear, mild, mild-to-moderate, moderate-to-severe, severe for a mNAPSI of 0, 1, 2, 3–4, 5–13
6	PASI	For each of the four body areas (upper limbs, lower limbs, head and trunk) erythema, scaling and thickening were defined as clear, mild, mild-to-moderate, moderate-to-severe or severe on a scale from 0 to 4. The affected body areas were rescaled from a 0–6 scale onto the same scale of 0–4 (0 (clear), 1 (mild), 2 (mild-to-moderate), 3–4 (moderate-to-severe), 4–6 (severe))

LEI, Leeds Enthesitis Index; mNAPSI, modified nail psoriasis severity index; PASI, psoriasis area severity index; PsA, psoriatic arthritis.