Reliability, validity and responsiveness of the syncope functional status questionnaire.
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.
van Dijk
Nynke
N
Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. n.vandijk@amc.uva.nl
Boer
Kimberly R
KR
Wieling
Wouter
W
Linzer
Mark
M
Sprangers
Mirjam A
MA
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