Cross-Cultural Validity, Reliability, and Psychometric Properties of the Persian Version of the Scales for Outcomes in Parkinson’s Disease-Psychosocial Questionnaire

Table 5

Validity, reliability, and psychometric properties of the SCOPA-PS in different languages/cultures (two different coefficients are reported for some indices to show the lowest and highest item-specific calculated reliability).

Authors	Year	Country/language	Reliability		Validity
			Internal consistency (Spearman R)	Internal consistency (Cronbach’s alpha)	Correlation coefficient with HADS (anxiety)	Correlation coefficient with HADS (depression)	Correlation coefficient with HRQoL (PDQ-39)*
Marinus et al. [14]	2003	The Netherlands/Dutch	0.24 (item 5) 0.67 (item 7)	0.83	0.61	0.62	0.82
Carod-Artal et al. [16]	2006	Brazil/Brazilian and Portuguese	0.43 (item 10); 0.73 (item 9)	0.84	0.50	0.47	0.73
Virués-Ortega et al. [8]	2009	Argentina, Paraguay, Ecuador, Brazil/Spanish and Portuguese	0.43 (item 10); 0.71 (item 9)	0.87	0.62	0.61	0.82
Knudsen et al. [15]	2007	Germany/German	0.35 (item 5) 0.77 (item 6)	0.90	0.76	0.76	0.86
Current study	2013	Iran/Persian	0.55 (item 5) 0.76 (item 7)	0.87	0.64	0.71	0.82

∗The reported correlation coefficients refer to the total score of the PDQ-39 questionnaire.