Table 2.

Pearson r correlation coefficients for two indices and 18 signs of speech and prosody deficits in 66 participants meeting nonmarginal pause marker (PM) criteria for childhood apraxia of speech (CAS) and 19 participants meeting nonmarginal PM criteria for adult-onset apraxia of speech (AAS).

Source	Competence-precision stability analytics			Method			Group
	Competence	Precision	Stability	Perceptual		Acoustic	CAS (n = 66)		AAS (n = 19)
				Transcription	PVSP		r	p	r	p
Indices
Speech competence index (SCI)	X			X	X	X	.116	.354	.251	.300
Precision stability index (PSI)		X	X	X	X	X	.189	.129	.380	.109
SCI with PSI							.608	.000	.421	.073
Speech
Vowels
Lengthened diphthongs and mid vowel		X				X			.572	.010
Lengthened corner vowels		X				X			.503	.028
Lengthened syllables		X				X	.343	.005	.567	.011
Consonants
Percent consonants correct revised	X			X					.371	.118
Percent consonants correct—late 8	X			X					.385	.104
Absolute substitution index	X			X					.357	.133
Absolute distortion index—late 8		X		X					.328	.170
Square root second moment for /s/ initial singleton		X				X			−.398	.102
More diffuse /s/ initial, /z/ final		X				X			−.435	.063
Lengthened consonant clusters		X				X	.441	.001	.597	.007
Prosody
Rate
Slow	X					X	.412	.001
Slow Articulation		X				X	.336	.006	.473	.041
Stress
Inappropriate	X				X				.539	.017
Laryngeal quality
Percent appropriate laryngeal quality	X				X				.454	.051
Jitter		X				X			.419	.074
Shimmer		X				X			.384	.105
Harmonics-to-noise ratio		X				X			.405	.086
Resonance quality
Lowered F2 high vowels		X				X			.321	.180

Note. PVSP = Prosody–Voice Screening Profile (Shriberg, Kwiatkowski, & Rasmussen, 1990).