Abstracts

Rationale: Health-related quality of life (HRQOL) assessments are ideally elicited directly, but for children or among cognitively impaired, proxy ratings may be used. Understanding whether self- versus proxy- perspectives produce different results and why is important for planning research studies that focus on these outcomes. We examine differences in results when using child versus parent report of the child’s HRQOL, in a group of children with epilepsy and controls. Methods: In a prospective, community-based study of newly diagnosed childhood epilepsy, HRQOL of 143 pairs of children 8-9 years after the initial diagnosis of epilepsy (cases) and of sibling controls was assessed using the self-administered Child Health Questionnaire (CHQ), a generic HRQOL measure (87 items in 11 subscales, 2 global items). The same parent rated HRQOL of a case and of the sibling control using the CHQ parent version (50 items in 12 subscales, 2 global items, 2 summary scores). Because child and parent CHQ versions contain similar but not identical items and scales, direct score comparisons across these versions is invalid. Thus, we used t-tests to compare HRQOL differences across the 11 subscales of the CHQ child version as self-reported by the case and sibling control. We compared HRQOL of the case and sibling control by testing differences across the 12 CHQ parent version subscales, reflecting differences in the parent’s perspectives of HRQOL of the case and of the sibling control. A sensitivity analysis was performed excluding 29 complicated cases (remote symptomatic or epileptic encephalopathy), generally associated with more severe neurological impairment. Results: Cases had a mean age of 12.6 years (range 8-19); 45% were female. Sibling controls had a mean age of 12.0 years (range 6-17); 58% were female. The mean age of parents was 41 years; 91% were female; 77% were employed; 72% had some college education; 80% were white. There were no differences between self-reported case and control HRQOL scores on 9 of 11 CHQ subscales; cases reported worse HRQOL compared to sibling controls on 2 subscales: physical functioning (p=0.01) and role limitations-physical health (p=0.04). In contrast, parent ratings of HRQOL of the case relative to sibling control were significantly higher (better) for sibling controls compared to cases on 10 of 12 subscales, both summary scores, and global general health item (all p ≤ 0.02). Excluding 29 complicated cases from analyses, findings were similar except that child and sibling control self-reports of HRQOL were now no different on all 11 CHQ subscales. Conclusions: Children with epilepsy report HRQOL comparable to that of healthy sibling controls, but parents rate children with epilepsy as having lower HRQOL than sibling controls. The reasons for this are not clear; however, until these differences are satisfactorily resolved, the source of HRQOL ratings should be weighed carefully when selecting measures in childhood epilepsy studies.