Cultural adaptation and psychometric properties of the Patient-weighted Quality of Life in Epilepsy 31 Inventory (QOLIE-31P) in Argentina.

OBJECTIVE: This study presents the cultural and linguistic adaptation and psychometric properties of the Argentine version of the Quality of Life in Epilepsy Inventory (QOLIE-31P) scale. METHODS: An instrumental study was carried out. A version of QOLIE-31P translated into Spanish was provided by the original authors. To assess the content validity, evaluation of expert judges was requested, and the degree of agreement was determined. The instrument was administered to 212 people with epilepsy (PWE) of Argentina, together with the BDI-II, B-IPQ and a sociodemographic questionnaire. A descriptive analysis of the sample was carried out. Discriminative capacity of the items was performed. Cronbach's alpha was calculated to assess reliability. To study the dimensional structure of the instrument, a confirmatory factorial analysis (CFA) was performed. Convergent and discriminant validity was tested through mean difference tests, linear correlation, and regression analysis. RESULTS: Aiken's V coefficients ranged between .90 and 1 (acceptable), which allows to state that a conceptually and linguistically equivalent version of the QOLIE-31P was reached. Cronbach's Alpha of 0.94 was obtained for the Total Scale (optimal). As a result of CFA, 7 factors were obtained, being the dimensional structure similar to the original version. Also, unemployed PWE reported significant lower scores than employed PWE. Finally, QOLIE-31P scores negatively correlated with depression symptom severity and negative illness perception. CONCLUSION: The Argentine version of the QOLIE-31P is a valid and reliable instrument, presenting good psychometric properties, such as high internal consistency and a dimensional structure similar to that of the original version.