Research in normal and disordered phonology requires measures of speech production that are biolinguistically appropriate and psychometrically robust. Their conceptual and numeric properties must be well characterized, particularly because speech measures are increasingly appearing in large-scale epidemiologic, genetic, and other descriptive-explanatory database studies. This work provides a rationale for extensions to an articulation competence metric titled the Percentage of Consonants Correct [PCC; Shriberg & Kwiatkowski, 1982; Shriberg, Kwiatkowski, Best, Hengst, & Terselic-Weber, 1986], which is computed from a 5- to 10-minute conversational speech sample. Reliability and standard error of measurement estimates are provided for 9 of a set of 10 speech metric including the PCC. Discussion includes rationale for selecting one or more of the 10 metrics for specific clinical and research needs.

Speech and prosody-voice profiles for 15 male speakers with High-Functioning Autism (HFA) and 15 male speakers with Asperger syndrome (AS) were compared to one another and to profiles for 53 typically developing male speakers in the same 10- to 50-years age range. Compared to the typically developing speakers, significantly more participants in both the HFA and AS groups had residual articulation distortion errors, uncodable utterances due to discourse constraints, and utterances coded as inappropriate in the domains of phrasing, stress, and resonance. Speakers with AS were significantly more voluble than speakers with HFA, but otherwise there were few statistically significant differences between the two groups of speakers with pervasive developmental disorders. Discussion focuses on perceptual-motor and social sources of differences in the prosody-voice findings for individuals with Pervasive Developmental Disorders as compared with findings for typical speakers, including comment on the grammatical, pragmatic, and affective aspects of prosody.

We estimate the prevalence of speech delay (L.D. Shriberg, D. Austin, B. A. Lewis, J. L. McSweeny, & D. L. Wilson, 1997b) in the United States on the basis of findings from a demographically representative population subsample of 1,328 monolingual English-speaking 6-year-old children. All children's speech and language had been previously assessed in the "Epidemiology of Specific Language Impairment" project (see J. B. Tomblin et al., 1997), which screened 7,218 children in stratified cluster samples within 3 population centers in the upper Midwest. To assess articulation, the Word Articulation subtest of the Test of Language Development-2: Primary (Newcomer & Hammill, 1988) was administered to each of the 1,328 children, and conversational speech samples were obtained for a subsample of 303 (23%) children. The 6 primary findings are as follows: (a) The prevalence of speech delay in 6-year-old children was 3.8%; (b) speech delay was approximately 1.5 times more prevalent in boys (4.5%) than girls (3.1%); (c) cross-tabulations by sex, residential strata, and racial/cultural backgrounds yielded prevalence rates for speech delay ranging from 0% to approximately 9%; (d) comorbidity of speech delay and language impairment was 1.3%, 0.51% with Specific Language Impairment (SLI); (e) approximately 11-15% of children with persisting speech delay had SLI; and (f) approximately 5-8% of children with persisting SLI had speech delay. Discussion includes implications of findings for speech-language phenotyping in genetics studies.

This report describes three extensions to a classification system for pediatric speech sound disorders termed the Speech Disorders Classification System (SDCS). Part I describes a classification extension to the SDCS to differentiate motor speech disorders from speech delay and to differentiate among three subtypes of motor speech disorders. Part II describes the Madison Speech Assessment Protocol (MSAP), an approximately two-hour battery of 25 measures that includes 15 speech tests and tasks. Part III describes the Competence, Precision, and Stability Analytics (CPSA) framework, a current set of approximately 90 perceptual- and acoustic-based indices of speech, prosody, and voice used to quantify and classify subtypes of Speech Sound Disorders (SSD). A companion paper, Shriberg, Fourakis, et al. (2010) provides reliability estimates for the perceptual and acoustic data reduction methods used in the SDCS. The agreement estimates in the companion paper support the reliability of SDCS methods and illustrate the complementary roles of perceptual and acoustic methods in diagnostic analyses of SSD of unknown origin. Examples of research using the extensions to the SDCS described in the present report include diagnostic findings for a sample of youth with motor speech disorders associated with galactosemia (Shriberg, Potter, & Strand, 2010) and a test of the hypothesis of apraxia of speech in a group of children with autism spectrum disorders (Shriberg, Paul, Black, & van Santen, 2010). All SDCS methods and reference databases running in the PEPPER (Programs to Examine Phonetic and Phonologic Evaluation Records; [Shriberg, Allen, McSweeny, & Wilson, 2001]) environment will be disseminated without cost when complete.

A companion paper includes rationale for the use of 10 metrics of articulation competence in conversational speech (Shriberg, Austin Lewis, McSweeny, & Wilson, 1997). The present paper reports lifespan reference data for these measures using records from a total of 836 3- to 40(+)-year-old speakers with normal and disordered speech. The reference data are subdivided by diagnostic classification based on extensions to an instrument titled the Speech Disorders Classification System (SDCS; Shriberg, 1993). Appendices provide procedural information on the SDCS and statistical rationale for the reference data.