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Parkinson’s Disease Sleep Scale:
Validation Study of a
Spanish Version
Pablo Martı ´nez-Martı ´n, MD, PhD,
1
*
Carlos Salvador, MD,
2
Luis Mene ´ndez-Guisasola, MD,
2
Sonia Gonza ´lez, Psychol, PhD,
2
Aurelio Tobı ´as, MSc, CStat,
1
Javier Almaza ´n, RN,
1
and K. Ray Chaudhuri, MD, PhD
3
1
Neuroepidemiology Unit, National Centre for Epidemiology,
Carlos III Institute of Public Health, and the Spanish
Network HOHSR, Madrid, Spain;
2
Movement Disorders
Unit, Asturias Central Hospital, Oviedo, Spain;
3
Department
of Neurology, King’s College and University Hospital
Lewisham, London, United Kingdom
Abstract: The Parkinson’s Disease Sleep Scale (PDSS) is the
first published bedside clinical tool to specifically measure
sleep disturbances in Parkinson’s disease (PD). The objec-
tive of the present study was to carry out a metric analysis
of a Spanish version (PDSS-SV) using a cross-sectional
study of 100 PD patients who participated in the study.
Usual measures for PD and mental status were applied by
neurologists. Patients completed the Epworth Sleepiness
Scale, Parkinson’s Disease Questionnaire-39 Items (PDQ-
39), and PDSS-SV. PDSS internal consistency (Cronbach’s
, 0.77; significant item-total correlation for 11 items) was
satisfactory. PDSS showed high test–retest reliability (in-
traclass correlation coefficient for items, 0.79 – 0.99; for
total score, 0.94). Standard error of measurement was 9.80
(crossover) and 5.01 (longitudinal). Scores were distributed
uniformly, with low floor and ceiling effect (1%). PDSS
scores were correlated significantly with depression (Ham-
ilton Depression Rating Scale, r
S
0.55; P < 0.0001) and
quality of life (PDQ-39 Summary Index, r
S
0.26; P
0.007), but not with clinical variables. Self-perception of
mood disorder, pain, or hallucinations correlated individu-
ally with PDSS scores, and a factor explaining 65% of the
variance was found. The assessment of PD sleep disorders
with the PDSS met some basic standards required for
health status measures. © 2004 Movement Disorder Society
Key words: PDSS-Spanish Version; validation; sleep disor-
der; Parkinson’s disease
*Correspondence to: Dr. P. Martı ´nez-Martı ´n, Unidad de Neuroepi-
demiologı ´a, Centro Nacional de Epidemiologı ´a, Instituto de Salud
Carlos III, C/Sinesio Delgado, 6, 28029 Madrid, Spain.
E-mail: pmartinez@isciii.es
Received 2 October 2003; Revised 7 February 2004; Accepted 24
February 2004
Published online 27 April 2004 in Wiley InterScience (www.
interscience.wiley.com). DOI: 10.1002/mds.20144
1226 P. MARTI
´
NEZ-MARTI
´
N ET AL.
Movement Disorders, Vol. 19, No. 10, 2004