Single-item measure for assessing quality of life in children with drug-resistant epilepsy.

Objective: The current study investigated the psychometric properties of a single-item quality of life (QOL) measure, the Global Quality of Life in Childhood Epilepsy question (G-QOLCE), in children with drug-resistant epilepsy.

Method: Data came from the Impact of Pediatric Epilepsy Surgery on Health-Related Quality of Life Study (PESQOL), a multicenter prospective cohort study (n = 118) with observations collected at baseline and at 6 months of follow-up on children aged 4-18 years. QOL was measured with the QOLCE-76 and KIDSCREEN-27. The G-QOLCE was an overall QOL question derived from the QOLCE-76. Construct validity and reliability were assessed with Spearman's correlation and intraclass correlation coefficient (ICC). Responsiveness was examined through distribution-based and anchor-based methods.

Results: The G-QOLCE showed moderate (r ≥ 0.30) to strong (r ≥ 0.50) correlations with composite scores, and most subscales of the QOLCE-76 and KIDSCREEN-27 at baseline and 6-month follow-up. The G-QOLCE had moderate test-retest reliability (ICC range: 0.49-0.72) and was able to detect clinically important change in patients' QOL (standardized response mean: 0.38; probability of change: 0.65; Guyatt's responsiveness statistics: 0.62 and 0.78). Caregiver anxiety and family functioning contributed most strongly to G-QOLCE scores over time.

Significance: Results offer promising preliminary evidence regarding the validity, reliability, and responsiveness of the proposed single-item QOL measure. The G-QOLCE is a potentially useful tool that can be feasibly administered in a busy clinical setting to evaluate clinical status and impact of treatment outcomes in pediatric epilepsy.