Interpretation of speech science measures.

There are a variety of objective measures that can aid in diagnosis, selection of goals for therapy, and measurement of progress. Much of the instrumentation that is necessary to perform these measures is available for use in microcomputers, so it is within the budgets of most clinics and school systems. Although the measures described above are objective, the clinician must be cautious in their interpretation. A number of these measures are maximum performance tests of speech. Kent, Kent, and Rosenbek (1987) note that the database on these types of measurements is inadequate. In addition, performance is highly variable and dependent on factors such as client motivation, instructions provided, and whether the client is given practice first. For this reason, the clinician must consider standard deviations as well as means when using the normative data. The preceding review is not intended to be exhaustive, nor is it intended to provide enough information for clinicians to be able to perform these measurements. The intent is to describe the potential clinical utility of the measures and to spark the interest of clinicians so they will persue the matter further. It is also not the intent of this article to encourage clinicians to stop using perceptual judgments in the clinic. Pannbacker and Middleton (1990) advocate the use of both perceptual and objective measures in assessing velopharyngeal insufficiency; however, these combined measures should be considered in the diagnosis of any speech disorder. Ultimately, it is the degree to which speech sounds deviant to a naive listener that determines whether an individual's speech is a problem.