Table 2.

Bortoluzzi’s Attribution Algorithm, Categorization, and Weighting of Items Incorporated into the Algorithm.

	Item	Score
Item 1.	Time of the onset of NP event with respect to SLE clinical onset
	Before (>6 months before SLE onset)	0
	Concomitant (within 6 months of SLE onset)	3
	After (>6 months of SLE event)	2
Item 2.	Minor or not specific NP events as defined by Ainiala
	Present	0
	Absent	3
Item 3.	Confounding factors or not SLE-related associations as defined by the ACR glossary
	None or not applicable	2
	Present (one confounding factor)	1
	Present (more than one confounding factor)	0
Item 4.	Additional (or favoring factors)
	None or not applicable	0
	Present (one additional or favoring factor)	1
	Present (more than one additional or favoring factor)	2

ACR, American College of Rheumatology; NP, neuropsychiatric; SLE, systemic lupus erythematosus.