Reliability and validity of the Thai pediatric quality of life inventory™ 3.0 neuromuscular module

BACKGROUND: Neuromuscular disorders (NMDs) are chronic illnesses that adversely impact the lives of patients and their families. The Pediatric Quality of Life™ 3.0 Neuromuscular Module (PedsQL™ 3.0 NMM) was designed to assess health-related quality of life (HRQoL) among children with NMDs. The objective of this cross-sectional study is to evaluate the reliability and validity of the PedsQL™ 3.0 NMM Thai version. METHODS: Formal permission to translate the PedsQL™ 3.0 NMM into Thai language was granted by the inventor, and the translation process followed linguistic translation guidelines. The PedsQL™ 3.0 NMM Thai version was administered to children with NMD and their parents/caregivers at the Division of Neurology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. Re-test was performed within 2–4 weeks after the initial test. RESULTS: One hundred and three children with NMD and their parents or caregivers were enrolled. Internal reliability as measured by Cronbach’s alpha was > 0.7 (total score: child α = 0.88, parent α = 0.91). Test-retest reliability showed good agreement with an intraclass correlation coefficient (ICC) of 0.69 and 0.82 for the total score of the child report and the parent report, respectively. The mean (SD) quality of life total score for the child self-report was 74.9 (13.9) among ambulatory patients, and 60.7 (15.2) among non-ambulatory patients (maximum quality of life score is 100). The mean total quality of life score for the parent proxy-report was 70 (14.5) among ambulatory patients, and 55.2 (18.3) among non-ambulatory patients. The child total score was in good agreement with the parent/caregiver total score. CONCLUSIONS: PedsQL™ 3.0 NMM Thai version is a reliable and valid measure of HRQoL in Thai children with NMDs.