Document Type
Article
Publication Date
2011
College/Unit
School of Pharmacy
Department/Program/Center
Pharmaceutical Sciences
Abstract
Background
Because of the subjective nature of Restless Legs Syndrome (RLS) symptoms and the impact of these symptoms on sleep, patient-reported outcomes (PROs) play a prominent role as study endpoints in clinical trials investigating RLS treatments. The objective of this study was to validate a new measure, the Post Sleep Questionnaire (PSQ), to assess sleep dysfunction in subjects with moderate-to-severe RLS symptoms.
Methods
Pooled data were analyzed from two 12-week, randomized, placebo-controlled trials of gabapentin enacarbil (N = 540). At baseline and Week 12, subjects completed the PSQ and other validated health surveys: IRLS Rating Scale, Clinical Global Impression of Improvement (CGI-I), Profile of Mood States (POMS), Medical Outcomes Study Scale-Sleep (MOS-Sleep), and RLS-Quality of Life (RLSQoL). Pooled data were used post hoc to examine the convergent, divergent, known-group validity and the responsiveness of the PSQ.
Results
Convergent validity was demonstrated by significant correlations between baseline PSQ items and total scores of IRLS, POMS, RLSQoL, and the MOS-Sleep Scale (p ≤ 0.007 each). Divergent validity was demonstrated through the lack of significant correlations between PSQ items and demographic characteristics. Correlations (p < 0.0001) between RLS severity groups and PSQ items demonstrated known-group validity. Mean changes in investigator- and subject-rated CGI-I scores for each PSQ item (p < 0.0001) demonstrated the PSQ's responsiveness to patient change as reported by their care provider.
Conclusions
Although these analyses were potentially limited by the use of clinical trial data and not prospective data from a study conducted solely for validation purposes, the PSQ demonstrated robust psychometric properties and is a valid instrument for assessing sleep and sleep improvements in subjects with moderate-to-severe RLS symptoms.
Digital Commons Citation
Canafax, Daniel M.; Bhanegaonkar, Abhijeet; Bharmal, Murtuza; and Calloway, Michael, "Validation of the post sleep questionnaire for assessing subjects with restless legs syndrome: results from two double-blind, multicenter, placebo-controlled clinical trials" (2011). Faculty & Staff Scholarship. 2744.
https://researchrepository.wvu.edu/faculty_publications/2744
Source Citation
Canafax, D.M., Bhanegaonkar, A., Bharmal, M. et al. Validation of the post sleep questionnaire for assessing subjects with restless legs syndrome: results from two double-blind, multicenter, placebo-controlled clinical trials. BMC Neurol 11, 48 (2011). https://doi.org/10.1186/1471-2377-11-48
Comments
© 2011 Canafax et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.