Validation of the Pediatric Quality of Life Inventory 3.0 Cerebral Palsy Module (Parent Form) for use in Türkiye

OBJECTIVES: This study was planned to test the reliability and validity of the Turkish version of the Pediatric Quality of Life Inventory (PedsQL) 3.0 cerebral palsy (CP) module (parent form) in children with CP. PATIENTS AND METHODS: In the validation study conducted between June 2007 and June 2009, 511 children (299 normal children, 212 children with CP) were assessed by the seven scales of PedsQL [daily activities (DA), school activities (SA), movement and balance (MB), pain and hurt (PH), fatigue (F), eating activities (EA), and speech and communication (SC)]. Reliability was tested by internal consistency and person separation index (PSI); internal construct validity by Rasch analysis and external construct validity by correlation with the Gross Motor Function Classification System (GMFCS) and Functional Independence Measure for Children (WeeFIM). RESULTS: Only 13 children with CP completed the inventory by themselves and thus were excluded. Consequently, 199 children with CP (113 males, 86 females; mean age: 7.3±4.2 years; range, 2 to 18 years) and 299 normal children (169 males, 130 females; mean age: 9.4±4.0 years; range, 2 to 17 years) were included in the final analysis. Reliabilities of the seven scales of the PedsQL 3.0 CP module were adequate, with Cronbach’s alphas between 0.66 and 0.96 and the PSI between 0.672 and 0.943 for the CP group. In Rasch analysis, for each scale, items showing disordered thresholds were rescored; then testlets were created to overcome local dependency. Internal construct validity of the unidimensional seven scales was good with the mean item fit of -0.107±1.149, 0.119±0.818, 0.232±1.069, -0.442±0.672, 0.221±0.554, -0.091±0.606, and -0.333±1.476 for DA, SA, MB, PH, F, EA, and SC, respectively. There was no differential item functioning. External construct validity of the instrument was confirmed by expected moderate to high correlations with WeeFIM and GMFCS (Spearman’s r=0.35-0.89). CONCLUSION: Turkish version of the PedsQL 3.0 CP module is reliable, valid, and available for use in clinical setting to evaluate health-related quality of life of children with CP.