Table 4.

Spearman Rank Order Correlations and Weighted Kappa Coefficients: Association and Agreement Between TETRAS and WHIGET Assessments.

ITEMS	SPEARMAN’S RANK ORDER CORRELATIONa	WEIGHTED KAPPAb
		FOUR LEVELc	TWO LEVELd
Spiral, dominant	0.89***	0.83	0.86
Spiral, non-dominant	0.85***	0.76	0.64
Finger to nose, dominant	0.78***	0.78	0.77
Finger to nose, non-dominant	0.80***	0.76	0.78
Outstretched, dominant	0.96***	0.99	0.98
Outstretched, non-dominant	0.93***	0.90	0.90
Wingbeat, dominant	0.95***	0.96	1.00
Wingbeat, non-dominant	0.93***	0.95	0.92

Note: N = 79; *** p ≤ 0.001.

^aRank order correlations represent associations between TETRAS and WHIGET numerical scores assigned to cases.

^bKappa coefficient values of <0.00 are interpreted as poor agreement, of 0.00 to 0.20 as slight agreement, of 0.21 to 0.40 as fair agreement, of 0.41 to 0.60 as moderate agreement, of 0.61 to 0.80 as substantial agreement, and of 0.81 to 1.0 as near perfect agreement [36].

^cThe four level weighted Kappa coefficients represent agreement between cases’ assignment to four tremor severity categories (no tremor, mild tremor, moderate tremor, severe tremor) based on TETRAS numerical scores, and cases’ assignment to those same four tremor severity categories based on WHIGET numerical scores.

^dThe two level weighted Kappa coefficients represent agreement between cases assignment to two tremor severity categories (no tremor/mild tremor versus moderate tremor/severe tremor) based on TETRAS numerical scores, and cases’ assignment to those same two tremor severity categories based on WHIGET numerical scores.