The Swedish SCOPA-SLEEP for assessment of sleep disorders in Parkinson’s disease and healthy controls
SCOPA-SLEEP is a rating scale for night-time sleep and daytime sleepiness (DS) proposed for use among people with Parkinson’s disease (PD) as well as others. We translated it into Swedish and assessed its psychometric properties in PD and age-matched healthy controls.
Following translation according to the dual-panel approach, the Swedish SCOPA-SLEEP was field-tested regarding comprehensibility, relevance and respondent burden (n = 20). It was then psychometrically tested according to classical test theory (data completeness, scaling assumptions, targeting, reliability and construct validity) using data from 149 people with PD and 53 age-matched healthy controls from the prospective Swedish BioFINDER study.
SCOPA-SLEEP took a mean of 3.5 min to complete and was considered easy to use and relevant. Missing item responses were <8 %, corrected item–total correlations were ≥0.47 (except for one DS item among controls), factor analyses suggested one dimension per scale, floor/ceiling effects were ≤17 %, reliability was ≥0.85 except for the DS scale among controls (0.65) and construct validity was supported.
Observations concur with previous evaluations, thus providing initial support for the Swedish SCOPA-SLEEP among people with PD. Further studies are needed to establish its generic properties and to understand its measurement properties in better detail.
KeywordsParkinson’s disease Rating scale Reliability Sleep Translation Validity
The authors wish to thank the participants, translators and lay people for their cooperation, and S. Hall, Y. Surova, K. Johansson, J. Reimer and A. Höglund for data collection. The study was supported by the European Research Council, the Swedish Research Council, the Swedish Parkinson Foundation, the Swedish Parkinson Academy, the Basal Ganglia Disorders Linnaeus Consortium (BAGADILICO) at Lund University, the Swedish federal government under the ALF agreement, and Kristianstad University, Kristianstad, Sweden. The funding sources had no role in the design and conduct of the study; in the collection, analysis, interpretation of the data; or in the preparation, review, or approval of the manuscript.
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Conflict of interest
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