title: Reliability, validity and responsiveness of the syncope functional status questionnaire.
abstract: BACKGROUND
  Patients with transient loss of consciousness (TLOC) have poor health-related quality of life (HR-QoL).
  
  
  OBJECTIVE
  To test the reliability, validity, and responsiveness of the disease-specific Syncope Functional Status HR-QoL Questionnaire (SFSQ), which yields two summary scales--impairment score (IS) and fear-worry score (FWS).
  
  
  METHODS
  Cohort-study.
  
  
  METHODS
  503 adult patients presenting with TLOC.
  
  
  METHODS
  HR-QoL was assessed using the SFSQ and the Short Form-36 (SF-36) after presentation and 1 year later. To test reliability, score distributions, internal consistency, and test-retest reliability were assessed. To assess validity, scores on the SFSQ and the SF-36 were compared. Clinical validity was tested using known-group comparison. Responsiveness was assessed by comparing changes in SFSQ scores with changes in health status and clinical condition.
  
  
  RESULTS
  Response rate was 82% at baseline and 72% at 1-year follow-up. For all scales the full range of scores was seen. Score distributions were asymmetrical. Internal consistency was high (alpha = 0.88 for IS, 0.92 for FWS). Test-retest reliability was moderate to good for individual items and high for summary scales (inter-class correlation = 0.78 for both IS and FWS). Correlations between SFSQ scores and the SF-36 were modest. The SFSQ did not discriminate between patients differing in age and gender but did discriminate between patients differing in number of episodes and comorbid conditions. Changes in SFSQ scores were related to changes in health status and the presence of recurrences but did not vary by TLOC diagnosis.
  
  
  CONCLUSIONS
  The SFSQ is an adequately reliable, valid, and responsive measure to assess HR-QoL in patients with TLOC.
authors.affiliation: Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. n.vandijk@amc.uva.nl
authors.forename: Nynke
authors.initials: N
authors.lastname: van Dijk
authors.forename: Kimberly R
authors.initials: KR
authors.lastname: Boer
authors.forename: Wouter
authors.initials: W
authors.lastname: Wieling
authors.forename: Mark
authors.initials: M
authors.lastname: Linzer
authors.forename: Mirjam A
authors.initials: MA
authors.lastname: Sprangers
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life / Q000523:psychology; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D013575:Syncope / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology