title: Most of the Quality of Life in Essential Tremor Questionnaire (QUEST) psychometric properties resulted in satisfactory values.
abstract: OBJECTIVE
  This study sought to assess the psychometric attributes of the Quality of Life in Essential Tremor Questionnaire (QUEST) by undertaking an independent validation.
  
  
  METHODS
  This was an observational, multicenter, cross-sectional study carried out in Neurology Departments of general hospitals. The following assessments were applied: Louis Rating Scale, Clinical Assessment of Tremor, Clinical Global Impression of Severity (CGI-ET), Hospital Anxiety and Depression Scale (HADS), EQ-5D, and QUEST (Spanish version).
  
  
  RESULTS
  One hundred and eighteen consecutive patients were included. According to the CGI-ET, most of patients had mild (42.4%) or moderate (43.2%) impact of tremor on performing daily activities. Fully computable QUEST data were 60.2%. The QUEST Summary Index (QUEST-SI) displayed marginal floor or ceiling effect. On the whole, QUEST internal consistency and reproducibility were satisfactory (Cronbach's alpha values: 0.73-0.86; QUEST-SI intraclass correlation coefficient: 0.77). Factor analysis identified eight factors (73.6% of the variance) that could be grouped into six, relatively coincident with the questionnaire's dimensions. The QUEST-SI correlated moderately with the EQ-5D index (r(S)=-0.40), HADS-Depression (r(S)=0.39), and CGI-ET (r(S)=0.39), and strongly with the QUEST scale for self-evaluation of tremor severity (r(S)=0.63). The standard error of measurement was 8.00.
  
  
  CONCLUSIONS
  Apart from a substantial problem of acceptability, most of the tested psychometric attributes of the QUEST resulted satisfactory.
authors: Area of Applied Epidemiology, National Center for Epidemiology, and Consortium for Biomedical Research in Neurodegenerative Diseases (Centro de Investigación Biomédica en Red Enfermedades Neurodegenerativas-CIBERNED), Carlos III Institute of Health, CI, Sinesio Delgado, 6, 28029 Madrid, Spain. pmartinez@isciii.es
authors: Pablo
authors: P
authors: Martínez-Martín
authors: Félix Javier
authors: FJ
authors: Jiménez-Jiménez
authors: Esmeralda
authors: E
authors: Carroza García
authors: Hortensia
authors: H
authors: Alonso-Navarro
authors: Lluisa
authors: L
authors: Rubio
authors: Patricia
authors: P
authors: Calleja
authors: María
authors: M
authors: Díaz-Sánchez
authors: Julián
authors: J
authors: Benito-León
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000328:Adult; D020329:Essential Tremor / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life / Q000523:psychology*; D013030:Spain / Q000453:epidemiology; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D055815:Young Adult