Objective: The aim of this study was to develop and validate a brief version of the Quality of Life in Childhood Epilepsy Questionnaire (QOLCE). A secondary aim was to compare the results described in previously published studies using the QOLCE-55 with those obtained using the new brief version.
Methods: Data come from 373 children involved in the Health-related Quality of Life in Children with Epilepsy Study, a multicenter prospective cohort study. Item response theory (IRT) methods were used to assess dimensionality and item properties and to guide the selection of items. Replication of results using the brief measure was conducted with multiple regression, multinomial regression, and latent mixture modeling techniques.
Results: IRT methods identified a bi-factor graded response model that best fits the data. Thirty-nine items were removed, resulting in a 16-item QOLCE (QOLCE-16) with an equal number of items in all 4 domains of functioning (Cognitive, Emotional, Social, and Physical). Model fit was excellent: Comparative Fit Index = 0.99; Tucker-Lewis Index = 0.99; root mean square error of approximation = 0.052 (90% confidence interval [CI] 0.041-0.064); weighted root mean square = 0.76. Results that were reported previously using the QOLCE-55 and QOLCE-76 were comparable to those generated using the QOLCE-16.
Significance: The QOLCE-16 is a multidimensional measure of health-related quality of life (HRQoL) with good psychometric properties and a short-estimated completion time. It is notable that the items were calibrated using multidimensional IRT methods to create a measure that conforms to conventional definitions of HRQoL. The QOLCE-16 is an appropriate measure for both clinicians and researchers wanting to record HRQoL information in children with epilepsy.
Keywords: epilepsy; health-related quality of life; item response theory; measurement; rating scales.
Wiley Periodicals, Inc. © 2018 International League Against Epilepsy.