Development and cross-cultural translations of a 31-item quality of life in epilepsy inventory

Purpose: We report the development of a questionnaire to assess health-related quality-of-life (HRQOL) in people with epilepsy and the process of cross-cultural translations of the questionnaire. Methods: A sample of 304 adults with epilepsy from 25 seizure clinics in the United States was used to derive an abbreviated questionnaire focusing on epilepsy-related issues from a longer, 89-item instrument (QOLIE-89). A rigorous forward-backward-forward system was used for cross-cultural translation. Results: A 31-item questionnaire (QOLIE-31, version 1.0) resulted, comprising seven subscales covering general and epilepsy-specific domains. Subscale and total scores can be calculated. The subscales were grouped into two factors: Emotional/Psychological Effects (seizure worry, overall QOL, emotional well-being, energy/fatigue subscales) and Medical/Social Effects (medication effects, work-driving-social limits, cognitive function subscales). Cross-cultural translations were made from U.S.-English into Danish, Dutch, German, Canadian French, French, Italian, Spanish, Swedish, and U.K. English Versions 1.1. Conclusions: Our results support the reliability and validity of the QOLIE-31 (U.S.-English version 1.0) as a measure of HRQOLIE. Cross-cultural translations into nine other languages make it feasible to use the QOLIE-31 (version 1.1) in multinational clinical trials after validation in each population or concurrent with the clinical trial.