Table 3.

Arthritis scoring system for POLY JIA patients*

Score	Severity level	Arthritis
0	None	No joint involvement
1	Mild	1 to 10 active joints
2	Moderate	10 to 20 active joints
3	Severe	> 20 active joints

* Arthritis severity is scored differently for SJIA and POLY JIA patients, because the patterns of joint involvement differ between the two groups [33]. The arthritis scoring system is based on frequency analyses of numbers of active joints in early active SJIA [34] and in active POLY JIA [Sandborg C, not shown]. An active joint is defined as a joint with non-bony swelling, or limited range of motion with either tenderness or pain on motion.