Ian R. A. MacKay
Dept. of Linguist., Univ. of Ottawa, Ottawa, ON K1N 6N5, Canada
Ann W. Kummer
Children's Hospital Med. Ctr., Pavilion Bldg., Cincinnati, OH 45229-2899
The Kay Elemetrics nasometer measures nasalance, a parameter of speech that reflects the proportion of total acoustic energy that is emitted nasally, making it possible to infer velopharyngeal (VP) function noninvasively. Nasometric evaluation is potentially widely applicable in the clinical assessment of suspected VF impairment. For clinical use, a patient's mean nasalance on a passage of known phonetic composition must be compared to age-appropriate population norms. Most potential clinical subjects are young; many are preliterate. Passages for which norms have been established (Zoo, Rainbow, Nasal Sentences) are syntactically, semantically, and lexically complex, phonetically heterogeneous, phonologically mature, and long. Individual child subjects' nasalance scores, if obtained at all, are therefore likely to be contaminated by artifacts created through hesitation noises, filled pauses, phonetic deviance from normed target, age differences, and measurement errors induced by coaching procedures. Differences in phonetic content between normed and actual utterances are almost inevitable; they lead to uninterpretable results. This study reports a technique for obtaining clinically useful nasalance scores from young, preliterate subjects, even those evidencing phonological deficits or noncompliant behavior. Large-n norms for preschool and primary children are presented.