ObjectivesThe Parkinson’s Disease Sleep Scale-2 (PDSS-2) is an updated tool designed to identify specific sleep disturbances in individuals with Parkinson’s disease (PD). However, for its application in Brazil, a process of cross-cultural adaptation and validation of measurement properties was required. MethodsThis methodological study adapted the PDSS-2 to Brazilian Portuguese (PDSS-2-Br) and assessed its measurement properties (Internal consistency, test-retest reliability, measurement error, construct validity, and interpretability). The adapted scale was then tested on 2 occasions within an interval of 7 days, to 50 individuals with PD. Test–retest reliability was evaluated using kappa statistics (k) for the individual items, intraclass correlation coefficient (ICC) for the total scores, standard error of measurement (SEM), minimal detectable change (MDC) and Bland-Altman plot. Construct validity was assessed through Spearman correlation coefficients between the PDSS-2-Br and independent variables, while interpretability was evaluated by examining ceiling and floor effects. ResultsPDSS-2-Br showed satisfactory semantic, idiomatic, cultural, and conceptual equivalence. It also demonstrated good internal consistency (α=0.64), adequate test-retest reliability between items (κw 0.42-0.94, 95% CI=0.30-0.95) and total score (ICC=0.94; 95% CI=0.89-0.96), acceptable measurement error (SEM, 2.07 points; MDC, 5.74 points), absence of ceiling and floor effects, and 87,5% of pre-defined hypotheses were confirmed, indicating adequate construct validity (Spearman correlations coefficients for the rs=0.50, p<0.001) of the PDSS-2-Br. ConclusionThe measurement properties of the PDSS-2-Br are equivalent to those of the original version, and the scale has been validated and confirmed as reliable to measure sleep disorders among the Brazilian population with PD.
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