Validity and Reliability of the Persian Version of Parkinson’s Disease Sleep Scale-2

Abstract

Objective. Sleep problems are nonmotor symptoms in Parkinson’s disease that should be carefully evaluated for better management and treatment. Parkinson’s Disease Sleep Scale (PDSS-2) is one of the most reliable tools for measuring sleep difficulties in people with Parkinson’s disease. This study investigated the psychometric properties of the Persian version of PDSS-2. Methods. Four hundred and fifty-six people with Parkinson’s disease with a mean age ±standard deviation of 60.7 ± 11.3 years were engaged in this study. Acceptability was assessed by floor and ceiling effects. Dimensionality was measured by exploratory factor analysis. The convergent validity of PDSS-2 with the Hospital Anxiety and Depression Scale (HADS) was assessed. Internal consistency and test-retest reliability were assessed with Cronbach’s alpha and intraclass correlation coefficient (ICC), respectively. Results. No noticeable ceiling and floor effect was detected. The dimensionality analysis showed three factors. A high correlation was obtained between PDSS-2 and HADS (anxiety subscale). Excellent internal consistency with α = 0.94, and good test-retest reliability with ICC = 0.89 were obtained. Conclusion. This study showed that the Persian version of Parkinson’s Disease Sleep Scale has acceptable validity and reliability for measuring sleep disturbances in people with Parkinson’s disease.

Assessment of Psychometric Characteristics of Parkinson’s Disease Sleep Scale 2 and Analysis of a Cut-Off Score for Detecting Insomnia in Italian Patients with Parkinson’s Disease: A Validation Study

“…Therefore, considering the importance of sleep disturbances in managing PD patients, screening for them to set therapeutic strategies becomes a standard of care for clinicians. The Parkinson’s disease Sleep Scale version 2 (PDSS-2) is a scale specifically designed to assess sleep problems in PD patients [ 14 ] and has been validated in several languages: Hindi [ 15 ], Persian [ 16 ], Korean [ 17 ], Spanish [ 18 ], and Italian [ 19 ]. The scale shows an excellent psychometric property across languages, with Cronbach’s alpha values of 0.73 (English) [ 20 ], 0.8 (Hindi), 0.9 (Persian), 0.85 (Korean) , 0.84 (Spanish), and 0.77 (Italian).…”