Reliability of Parent Proxy-Report Measures of Quality of Life and Cognitive Functioning in Pediatric Sickle Cell Disease

Introduction: Parent proxy-report measures offer a convenient approach to assessing a child's functioning in daily life (e.g., quality of life, cognitive abilities) compared to more intensive methods of observation and neuropsychological assessment. However, it is unclear if parents should be considered more reliable reporters of certain domains of functioning over others. The current study examined level of agreement between parent proxy-report measures of child quality of life and child working memory function compared to child self-reported quality of life and neuropsychological assessment of working memory, respectively, in a sample of children with SCD. We hypothesized that parent proxy-reports of child quality of life would have a moderate to high level of agreement with child self-reports. We also hypothesized that parent proxy-reports of child working memory would demonstrate a low to moderate level of agreement with working memory as assessed by neuropsychological assessment.

Methods: Primary caregivers of children aged 7-16 with SCD reported on their child's quality of life by completing the 43-item Pediatric Quality of Life Inventory (PedsQL™) SCD Module parent proxy-report, rating items on a 5-point Likert scale (0 = never to 5 = almost always). Caregivers also completed the Behavior Rating Inventory of Execute Function (BRIEF) parent proxy-report form to rate their child's everyday cognitive functioning. The BRIEF Working Memory subscale (BRIEF-WM) was used as the parent-reported cognitive functioning variable of interest in analyses. Children completed the 43-item PedsQL™ SCD Module self-report form, rating items on a 5-point Likert scale (0 = never to 5 = almost always). Children also completed the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) Digit Span and Picture Span subtests to produce a working memory index (WMI). The WMI was used as the performance-based cognitive functioning variable of interest for analyses evaluating working memory function. Intraclass Correlation Coefficients (ICC) were calculated to measure agreement between parent proxy-report and child self-report of quality of life on the PedsQL™. A Pearson's correlation coefficient was calculated to measure the relationship between parent-reported working memory (i.e., BRIEF-WM) and working memory function as assessed by standard neuropsychological tests (i.e., WISC-V WMI).

Results: Eighty-seven caregivers of children with SCD (Mean age = 10.43, SD = 2.94; 58% female; 76% HbSS or HbS-beta⁰ thalassemia) completed reports on their child's QOL and working memory function. Parent proxy-reports of child quality of life had a mean of 67.09 (SD = 19.36), while child self-reports of QOL had a mean of 64.71 (SD = 20.69). The parent BRIEF-WM measure had a mean score of 61.40 (SD = 12.70) and child WISC-V WMI scores had a mean of 95.23 (SD = 13.61). A moderate degree of reliability was found between parent and child PedsQL™ total scores. The average measure ICC was 0.63 with a 95% confidence interval from 0.44 to 0.76 (F(86) = 2.71, p < .001). The relationship between parent ratings of child working memory (BRIEF-WM) the performance-based measures of working memory (WISC-V WMI) was not statistically significant (r = -0.20, p = 0.07).

Conclusions: Current results suggest that parents can reliably report on their child's quality of life. However, parent-reported observations of a child's working memory abilities were not statistically correlated with their child's performance-based measure of working memory. This suggests that while parents are often keen observers of their child's functioning in general, parent-report measures of cognitive abilities have limitations and may not reliably serve as a substitute to performance-based testing. Future research should assess whether parents can more reliably report on specific domains of cognitive functioning or whether working memory deficits (versus average or above average functioning) are more reliably identified by parent observation. Such studies will inform best practices for monitoring of cognitive functioning in youth with SCD and determine when a comprehensive performance-based cognitive assessment is needed.

No relevant conflicts of interest to declare.