Table B3.

Dysarthria Index (DI) and the five Dysarthria Subtype Indices (DSI).

DI and DSI: Individual
Linguistic domain	Sign no.	Description	Assessment mode a		DI sign values		Five DSI b
			P	A	z Score c	Code d	Ataxia	Spastic	Hyperkinetic	Hypokinetic	Flaccid
Vowels
	1	Increased percentage of vowels/diphthongs distortions	X				X (2)		X (2)
Consonants
	2	Number of nasal emissions	X								X (2)
	3	Increased percentage of weak consonants	X								X (1)
Vowels and consonants
	4	Increased Diacritic Modification Index class duration	X				X (1)		X (1)
Phrasing
	5	Increased slow/pause time	X						X (1)	X (2)
Rate
	6	Increased slow articulation/pause time	X				X (1)	X (2)	X (1)
	7	Decreased average syllable speaking rate (with pauses)		X			X (1)	X (2)	X (1)
	8	Decreased average syllable articulation rate (without pauses)		X			X (1)	X (2)	X (1)
	9	Increased fast rate	X							X (2)
	10	Decreased stability of syllable speaking rate		X					X (1)	X (2)
Stress
	11	Increased excessive/equal/misplaced stress	X				X (2)	X (1)
	12	Increased reduced/equal stress	X							X (2)
Loudness
	13	Decreased stability of Speech Intensity Index		X			X (2)		X (2)
	14	Increased stability of Speech Intensity Index		X				X (1)		X (2)	X (1)
	15	Increased soft	X							X (2)	X (1)
	16	Decreased Speech Intensity Index		X						X (2)	X (1)
Pitch
	17	Increased low pitch/glottal fry	X					X (2)	X (1)
	18	Increased low pitch	X					X (2)	X (1)
	19	Decreased F0 for all vowels and diphthongs		X				X (2)	X (1)
	20	Decreased range of char. F0 among vowels		X				X (1)	X (1)	X (2)	X (1)
	21	Decreased stability of F0 for all vowels and diphthongs		X			X (1)
Laryngeal quality
	22	Increased breathy	X							X (1)	X (2)
	23	Increased rough	X					X (1)	X (1)
	24	Increased strained	X					X (1)	X (1)
	25	Number of utterances with [TREM] (tremulous) comment	X						X (1)
	26	Increased break/shift/tremulous	X					X (2)	X (1)
	27	Increased multiple features	X					X (2)	X (2)
	28	Number of diplophonia	X								X (2)
	29	Increased % jitter for vowels		X			X (1)
	30	Decreased stability of jitter for vowels		X			X (1)
	31	Increased % shimmer for vowels		X			X (1)
	32	Decreased stability of shimmer for vowels		X			X (1)
Resonance quality
	33	Increased nasal	X					X (1)	X (1)	X (1)	X (2)
	34	Decreased F1 for /a/ (nasal)		X				X (1)	X (1)	X (1)	X (2)
		Unweighted total possible points					12	15	19	11	10
		Weighted total possible points					15	23	22	19	15
DI summary			DSI summary
No. of positive signs							Ataxia	Spastic	Hyperkinetic	Hypokinetic	Flaccid
No. of signs with data			Percentage of positive signs
Average sign z score			DSI (% nonpositive weighted)
DI (% nonpositive signs)			DSI percentile score

^a A = Acoustic; P = perceptual.

^b Very frequent: 80.0%–100%; frequent: 60.0%–79.9%; somewhat frequent: 40.0%–59.9%; somewhat infrequent: 20.0%–39.9%; infrequent: 0.0%–19.9%.

^c z scores referenced to age–sex matched, typically developing speakers (Potter et al., 2012; Scheer-Cohen et al., 2013). For the three “Number of” items (2, 25, and 28), this column has a count rather than a z score.

^d Code: 0 = not positive on variable; 1 = positive on variable (z score ≤ 1.50 or “Number of” ≥ 2).