Psychometric validation of the French version of the side-effects and life satisfaction inventory (SEALS) in epileptic patients: comparison with the QOLIE-31 inventory and a generic quality of life questionnaire

Abstract

A psychometric evaluation of a French version of the side-effects and life satisfaction inventory (SEALS) was carried out. SEALS was compared to the quality of life in epilepsy-31 questionnaire (QOLIE-31) and a generic, health-related quality-of-life questionnaire, the Nottingham health profile (NHP). The psychometric properties of SEALS, assessed in 190 adult subjects with epilepsy, included: acceptability, test-retest reliability and validity, multitrait analysis including internal consistency and item-to-scale correlations, construct validity using factor analysis and discriminative validity using associations with disease characteristics and treatment effects, and, correlations with NHP and QOLIE-31 scores for convergent and divergent validity. Both acceptability and reproducibility were good and internal consistency was high (Cronbach's alpha coefficient = 0.92). Factor analysis with varimax rotation identified five factors: the first, related to cognitive function accounted for 26.0% of the variance. Discriminative validity was good for most treatment characteristics (tolerability, seizure control, compliance) and clinical features (epilepsy type, seizure frequency and severity, depressive symptoms). Correlations with the NHP and QOLIE-31 scores were consistently strong. It was concluded that the psychometric properties of the French translation of SEALS were similar to the original English version. In addition, SEALS provides information on quality of life that is complementary to that obtained with QOLIE-31. In particular, with respect to the QOLIE-31, the SEALS provides information on cognitive and neuropsychological aspects of impairment of quality of life, whereas the QOLIE-31 has a broader scope, taking into account multiple aspects of quality of life in epilepsy.