Validation of the Thai SCOPA-sleep scale for assessment of sleep and sleepiness in patients with Parkinson's disease.

OBJECTIVE To validate the Thai version of the Scale for Outcomes in Parkinson 's disease-Sleep Scale (SCOPA-Sleep scale)for assessment of nighttime sleep problems (NSP) and daytime sleepiness (DS). MATERIAL AND METHOD A Thai version of SCOPA-Sleep scale has been developed with the permission of the originator. Fifty-one patients with Parkinson's disease were asked to complete the Thai SCOPA-Sleep scale (consisting of NSP and DS sections), plus the Pittsburg Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS). A second group of twenty patients completed the Thai SCOPA-Sleep scale, twice, two weeks apart. The reliability and validity were subsequently analyzed. RESULTS The Thai SCOPA-Sleep scale showed a Cronbach 's alpha coefficient of 0.87 and 0.74 for SCOPA-NSP and SCOPA-DS, respectively with no significant difference between initial and follow-up scores. The content validity of SCOPA-NSP and SCOPA-DS were 0.9 and 0.9, respectively. There was a strong correlation between the Thai SCOPA-NSP and PSQI as well as the Thai SCOPA-DS and ESS (p < 0.01 and p < 0.01, respectively). CONCLUSION The Thai SCOPA-Sleep scale is a reliable, valid instrument for assessing NSP and DS