Psychometric validation of the revised SCOPA-Diary Card: expanding the measurement of non-motor symptoms in parkinson's disease

Table 2 Standardized Factor Loadings from Alternative Confirmatory Factor Analyses Models

Revised SCOPA-DC Item	Two-Factor Model^┼		Three-Factor Model
	Factor 1	Factor 2	Factor 1 (Mobility)	Factor 2 (Physical Functioning)	Factor 3 (Psychological Functioning)
01. Walking	0.82		0.79
02. Changing position	0.92		0.98
03. Using your hands	0.68			0.74
04. Uncontrollable movements	-			0.67
05. Feelings of exhaustion or fatigue		0.80		0.77
06. Difficulty concentrating or remembering		0.76			0.95
07. Feelings of anxiety or panic		0.59			0.75
08. Unexplained pains		0.78		0.80
09. Difficulty swallowing		-		-
10. Frequent or urgent urination		0.69		0.72
11. Sweating too much		0.58		0.56
CFI/TLI	0.94/0.91		0.97/0.96
RMSEA (90% confidence interval)	0.09 (0.05, 0.13)		0.06 (0.00, 0.10)
SRMR	0.06		0.05

^┼ This model was obtained after model refinement: items 4 and 9 were excluded; items 6 and 7 were allowed to be correlated.
CFI = Comparative Fit Index, TLI = Tucker-Lewis Index, RMSEA = Root Mean Square Error of Approximation, SRMR = Standardized Root Mean Residual; SCOPA-DC = Scales for Outcomes of Parkinson's disease Diary Card. Threshold values indicating good fit: CFI and TFI: ≥ .95; RMSEA: < .06; SRMR: < .09.

ISSN: 1477-7525