Stages in the development and validation of a Belgian Dutch outcome tool for the perceptual evaluation of speech in patients with cleft palate

Abstract

OBJECTIVE : To develop and validate a Belgian Dutch outcome tool for the perceptual evaluation of speech in patients with cleft palate. SETTING : Cleft palate team in a tertiary university hospital. METHODS : The tool was based on the Cleft Audit Protocol for Speech–Augmented (John et al., 2006; Sell et al., 2009), with adaptations to some of the speech variables and the structured listening protocol. Following a preliminary listening experiment in phase 1, the tool was optimized. In the second phase, a listening experiment with 4 experienced listeners was set up to assess face validity, inter- and intrarater reliability and criterion validity. RESULTS : Results of phase 1 indicated good to very good inter- and intrarater reliability for the majority of the speech variables, good discriminant validity, and varying sensitivity and specificity based on a comparison with nasalance values and the Nasality Severity Index 2.0 (criterion validity). Results of phase 2 showed good to very good interrater reliability for 5 of the 14 variables and good intrarater reliability in 3 of the 4 experienced listeners. Sensitivity and specificity were sufficient, except the specificity of the hypernasality judgments in comparison with the nasalance values of the oral text. Overall, listeners positively judged the face validity of the tool. CONCLUSION : The 2-phase evaluation indicated varying validity and reliability results. Future studies will aim to optimize validity and reliability of the developed tool based on adaptations to the listening protocol, the addition of speech variables, and the inclusion of a more elaborate training.