PedsQL™ Cognitive Functioning Scale in youth with epilepsy: Reliability and validity

Objective: The objective of the study was to report on the internal consistency reliability and discriminant, concurrent and construct validity of the Pediatric Quality of Life Inventory™ (PedsQL™) Cognitive Functioning Scale as a brief generic cognitive functioning measure in youth with epilepsy.

Methods: The 6-item PedsQL™ Cognitive Functioning Scale and 23-item PedsQL™ 4.0 Generic Core Scales were completed by 221 pediatric patients ages 5-18 years with epilepsy and 336 parents of patients ages 2-18 years in a national field test study for the PedsQL™ Epilepsy Module. Parents also completed the 86-item Behavior Rating Inventory of Executive Function (BRIEF), a widely validated measure of executive functioning.

Results: The PedsQL™ Cognitive Functioning Scale evidenced excellent reliability (patient self-report α = 0.88; parent proxy-report α = 0.96), distinguished between youth with epilepsy and an age, gender, and race/ethnicity-matched healthy sample supporting discriminant validity with large effect sizes (~20-30 point score differences, P < 0.001), and demonstrated concurrent and construct validity, respectively, through large effect size intercorrelations with the BRIEF (Behavioral Regulation Index, Metacognition Index, Global Executive Composite Summary Scores rs = 0.43-0.67, P < 0.001) and the PedsQL™ Generic Core Scales (Total Scale Scores rs = 0.67-0.74, P < 0.001). Minimal clinically important difference (MCID) scores ranged from 5.92 to 8.80.

Conclusions: The PedsQL™ Cognitive Functioning Scale demonstrated excellent internal consistency reliability, discriminant, concurrent, and construct validity in youth with epilepsy and may be suitable as a brief generic patient-reported outcome (PRO) measure for clinical research, clinical trials, and routine clinical practice in pediatric epilepsy.