Correlation between the Perceptual Rating of Speech in Dutch Patients with Velopharyngeal Insufficiency and Composite Measures Derived from Mean Nasalance Scores

Abstract

Objective: To evaluate the potential clinical use of composite measures derived from mean nasalance scores. Procedure: Speech samples with a normal distribution of phonemes (normal text, NT) and speech samples free of nasal consonants (denasal text, DT) of 43 patients with perceived hypernasality were used. The overall grade of severity, hyperrhinophonia, audible nasal emission, misarticulations associated with velopharyngeal insufficiency and intelligibility were perceptually rated on separate visual analog scales. Mean nasalance scores were computed by the Nasometer for the same speech samples on which the perceptual ratings were performed. From the mean nasalance scores computed for the NT and DT passages the difference and the quotient were calculated. The advantage could be that the derived measures provide some normalization with regard to the performance of the individual speaker. Spearman correlation coefficients were computed between these composite measures and the perceptually rated parameters. The results were compared with the correlation coefficients between the mean nasalance scores and the ratings. Setting: The Institute of Phoniatrics, Utrecht University Hospital, The Netherlands. Results: The correlations between the composite measures and the perceptual ratings were generally lower than the correlations between mean nasalance scores and the ratings. Conclusion: Normalization of the nasalance scores did not enhance the correlation with the perceptual ratings in this study.