Health-related quality of life in patients with cleft palate : reproducibility, responsiveness and construct validity of the Dutch version of the VELO questionnaire

Abstract

OBJECTIVES : Recently, the Velopharyngeal Insufficiency (VPI) Effects on Life Outcomes (VELO) questionnaire, which evaluates the impact of speech and swallowing difficulties on health-related quality of life (HRQoL) in patients with VPI (Skirko et al., 2012), was translated to Dutch (Bruneel et al., 2017). The purpose of this study was to evaluate the reproducibility, responsiveness and construct validity of this Dutch version of the questionnaire. METHODS : To evaluate the reproducibility, 50 parents and 14 children with cleft palate re-completed the questionnaire after two weeks. Thirty-five parents and 8 children with cleft palate completed the VELO questionnaire after one year for the evaluation of the responsiveness. The correlation between age and the VELO questionnaire (construct validity), and the internal consistency (Cronbach's α) were re-determined based on the responses of 73 parents and 24 children. RESULTS : Based on descriptive statistics, results of the Wilcoxon signed rank-test, and the absolute (SEM) and relative (ICC) consistency, the questionnaire showed good reproducibility. VELO scores did not significantly differ after one year, neither when performing separate analyses for the intervention (speech therapy) and the non-intervention group. Correlations indicated higher HRQoL, as perceived by the parents, with increasing age. The reverse was the case for the youth report. Cronbach's α showed excellent internal consistency for both reports. CONCLUSIONS : The VELO questionnaire showed good reproducibility and internal consistency. Moreover, results reconfirmed the age effect on VELO scores. To understand the implications of the results regarding the questionnaire's responsiveness, future research should focus on the identification of factors influencing the patient's evolution in HRQoL.