Correspondence between Nasalance Scores and Listener Judgments of Hypernasality and Hyponasality

Abstract

The relationship between nasalance scores and perceptual judgments of hypernasality and hyponasality was examined for 74 subjects (51 with cleft palate and 23 noncleft controls). Twenty-nine of the 51 subjects with cleft palate had received pharyngeal flap surgery. Predictive analyses were performed to assess the sensitivity, specificity, and efficiency of the Nasometer as a screening instrument. The overall relationship between perceptual judgments of hypernasality and nasalance scores was good for the nonflap subjects when a nasalance cutoff score of 26 was used. A sensitivity coefficient of 0.67 and a specificity coefficient of 0.93 were obtained. Ninety-one percent of the nasometry-based classifications accurately reflected listener judgments of hypernasality. The correspondence between nasalance scores and clinical judgments of hyponasality was also good for the nonflap subjects when a nasalance cutoff score of 50 was used. Ninety-one percent of these classifications were consistent with the listener judgments. Efficiency of nasometry was poorer for the flap subjects.