Telephone validation of the Quality of Life in Epilepsy Inventory-89 (QOLIE-89)

Purpose: To assess the psychometric properties of the Quality of Life in Epilepsy Inventory-89 (QOLIE-89) administered via telephone and to compare these properties with data gathered through self-administration. Methods: A study of 139 patients with epilepsy was undertaken at three clinical sites in the United States. Patients participated in both telephone interview (T) and self-administration (S). Order effect was controlled through randomization (T-S and S-T). Twenty-eight S-T subjects participated in an assessment of the 2-week reproducibility of telephone interviews. Results: Internal consistency and test-retest reliability levels of the QOLIE-89 overall score were very high across method of administration (T = 0.98; S = 0.98; ICC of T = 0.96). Scores were significantly related to mood (Profile of Mood States, r = -0.76, for both methods, p < 0.001) and two indicators of epilepsy severity (seizure frequency in the past month, T: r = 0.52, p < 0.0001; S: r = 0.54, p < 0.0001; days since last seizure, T: r = 0.28, p < 0.001; S: r = 0.25, p < 0.01), with no significant differences in coefficients by method of administration. Performance of the measure was consistent for patients with unimpaired and impaired memory, using the River-mead Behavioural Memory Test, and across level of education. Conclusions. Results of this study indicate telephone interview is a viable option for evaluating HRQL in persons with epilepsy and support the reliability and validity of the QOLIE-89 regardless of method of administration.