Comparison of nasalance scores obtained from the Nasometer and the NasalView

Nasalance scores obtained from the Nasometer and the NasalView were compared for five different sentences.

Vowel content was controlled in the design of the five stimulus sentences. One sentence was loaded with high-front vowels, one with high-back vowels, one with low-front vowels, one with low-back vowels, and one contained a mixture of vowel types.

The subjects were 50 elementary school children ranging from kindergarten to sixth grade. Each subject was a native speaker of English, had no history of adenoidectomy, and was not currently enrolled in speech therapy services.

The main outcome measures were the nasalance scores obtained from the Nasometer and the NasalView for each of the five sentences.

There was a significant difference in the nasalance scores between the Nasometer and the NasalView for four of the five stimuli, but not all differences were in the same direction. For two stimuli, the Nasometer scores were significantly higher, and for two stimuli the NasalView scores were higher. Bivariate correlations between nasalance scores for individual stimuli were in the good range for the Nasometer but poor for the NasalView.

Speech stimuli weighted with different vowel types are differentially affected by the different acoustical filtering used in the Nasometer versus the NasalView. Nasalance scores obtained with the NasalView were qualitatively and quantitatively different from those obtained with the Nasometer. This suggests that the two machines provide different information, and the scores are not interchangeable.