Table 1.

The 10 items of the clinical activity score (CAS)

Pain	1 Painful, oppressive feeling on or behind the globe during the last 4 weeks
	2 Pain on attempted up, side, or down gaze during the last 4 weeks
Redness	3 Redness of the eyelid(s)
	4 Diffuse redness of the conjunctiva, covering at least one quadrant
Swelling	5 Swelling of the eyelid(s)
	6 Chemosis
	7 Swollen caruncle
	8 Increase of proptosis of ≥2 mm during a period of 1–3 months
Impaired function	9 Decrease of eye movements in any direction ≥5° during a period of 1–3 months
	10 Decrease of visual acuity of ≥1 line(s) on the Snellen chart (using a pinhole) during a period of 1–3 months

For each item present, one point is given. The sum of these points is the CAS