A preliminary validation of a dynamic speech motor assessment for Swedish-speaking children with childhood apraxia of speech

Figures & data

Table 1. Subtests and number of words/utterances in DYMTA-A and DYMTA-B, respectively.

DYMTA-A	Number of utterances	DYMTA-B	Number of utterances
1. CV	11	1. Simple syllables	13
2. VC	6	2. Voiced-voiceless contrast	6
3. CVCV	4	3. Dental-velar contrast	6
4. CVC	6	4. Stop-fricative contrast	6
5. CVC2	10	5. Consonant clusters	10
6. CV1CV2	6	6. Word stress	8
7. C1V1C2V2	6	7. Tonal word accent	6
8. Multisyllabic words	6	8. Multisyllabic words	10
		9. Increased length of utterance	6
	55		71

Table 2. Demographics and speech- language data for individual participants ordered by DYMTA-A scores within diagnostic groups..

Group	ID	DYMTA-A Total score	DYMTA-B Total score	Sex	Age (months)	PCC	PVC	PWC	GRAMBA	Receptive	OMS
SSD (non-CAS)	24	407	445	M	103	98	100	98	41	53^b	87
	16	407	408	M	57	89	97	72	43	94	97
	34	407	405	F	63	89	100	55	39	86	100
	6	406	433	M	61	86	99	58	44	98	100
	15	397	343	M	50	71	95	32	39	91	91
	10	395	373	M	59	62	91	25	41	97	98
	38	386	446	M	74	98	97	90	41	87	100
	14	381	404	M	58	79	96	40	44	99	96
	18	369	395	M	66	77	99	40	42	82	97
	8	361	335	F	50	63	98	25	43	63	94
	4	357	334	F	52	64	94	20	29	91	96
	18	340	311	M	59	65	92	28	39	45	89
mild CAS	33	391	367	M	58	81	97	42	42	99	95
	35	381	340	M	58	62	88	30	–^a	15*^a	77
	17	365	401	M	92	86	99	65	43	58	99
	1	361	354	F	57	74	92	38	43	99	95
	20	331	318	M	81	70	97	32	44	75	100
CAS	7	384	311	F	98	55	95	20	44	66	99
	9	375	323	M	91	75	95	28	42	21	99
	36	364	290	M	62	68	100	22	41	66	92
	19	359	318	F	88	59	95	20	40	70	98
	29	357	314	M	62	62	90	15	16^a	10	90
	23	348	341	F	106	77	95	52	38^a	39	95
	5	342	288	M	81	64	86	15	41	84	96
	39	333	299	F	61	59	96	25	42	18	79
	45	329	252	F	77	42	91	15	22^a	3^a	95
	2	321	313	M	74	48	92	10	42	93	96
	11	312	289	F	90	54	96	12	44	32	100
	21	295	267	M	81	49	96	8	44	84	99
	41	295	262	M	82	72	85	30	43	63	97
	13	289	267	M	64	48	95	10	38	96	98
	3	281	306	M	53	82	88	40	44	99	98
	12	280	269	F	90	49	96	15	44	45	98
	44	279	257	F	76	60	96	18	26^a	0^a	88
	37	274	225	M	61	34	94	10	37	86	100
	25	272	270	M	60	56	90	15	36	66	100
	40	269	190	M	68	42	94	5	34	95	97
	32	258	268	M	69	57	88	10	23^a	73	100
	26	256	273	M	54	56	92	10	41	58	74
	31	221	199	M	46	27	65	0	12^a	8*	92
	28	205	181	M	56	24	84	0	38	99	100
	30	186	129	M	45	32	85	5	24	10*	76
	42	165	110	F	67	31	62	2	36	61	93
	22	164	124	F	40	24	67	0	–^a	17*	71
	43	153	115	M	44	14	64	0	2^a	14*	71

ID: identification; PCC: percent consonant correct; PVC: percent vowels correct; PWC: percent words correct (PCC, PVC, and PWC are calculated from LINUS phonology test); Receptive = Test for Reception of Grammar (TROG2) for 4 years old and older (percentiles) and Språkligt Impressivt Test för barn (SIT) for 3-year-olds, with one exception (mean number of errors for 36–47 months is 14 and for 48–59 months 8 errors, of maximum score 46), *indicates SIT scores; GRAMBA: Grammatiktest för Barn (total score, maximum 44); OMS: oral motor score derived from VMPAC (from subtests focal oromotor control and sequencing maintenance control). F: female, M: male. Language scores followed by ^aare considered in the clinically impaired range, ^bthis child has word retrieval difficulties not captured in the GRAMBA score. Em dashes indicate missing values due to lack of child attention that prevented completion of the whole test.

Figure 1. Panel A and C illustrates performance on DYMTA-A total score and DYMTA-B total score, respectively, separately for children with CAS and nonCAS-SSD. In these figures, each individual is shown as a separate point. Panel B and D illustrates the ROC-curve for the DYMTA-A and DYMTA-B. Two potential cutoffs are illustrated in panel A, one based on the binomial logistic regression (dashed line) and one based on the positive likelihood ratio (dotted line) and the sensitivity and specificity pair related to these cutoffs are illustrated in panel B. Similarly, for panel C and D. The AUC is shown in panel B and D as the shaded area.

Table 3. Estimates of reliability for DYMTA-A and DYMTA-B total scores and subscores.

Measure	Intra-rater reliability		Inter-rater reliability
	Point-by-point agreement mean (range)	ICCs estimate [CI]	Point-by-point agreement mean (range)	ICCs estimate [CI]
DYMTA-A
Total score	0.98 (0.94–1.00)	0.99 [0.99, 1.00]	0.91 (0.84–0.97)	0.97 [0.88, 0.99]
Vowel accuracy	0.98 (0.91–1.00)	0.98 [0.93, 0.99]	0.92 (0.84–1.00)	0.82 [0.48, 0.94]
Artic accuracy	0.97 (0.87–1.00)	0.99 [0.99, 1.00]	0.91 (0.84–0.98)	0.98 [0.92, 0.99]
Prosody	0.99 (0.95–1.00)	0.88 [0.66, 0.96]	0.89 (0.73–1.00)	0.03 [−0.53, 0.57]
Consistency	0.98 (0.95–1.00)	0.99 [0.97, 1.00]	0.91 (0.82–0.98)	0.96 [0.88, 0.99]
DYMTA-B
Total score	0.95 (0.91–0.98)	0.99 [0.97, 1.00]	0.87 (0.79–0.91)	0.96 [0.89, 0.99]
Vowel accuracy	0.98 (0.92–1.00)	0.97 [0.92, 0.99]	0.90 (0.75–0.97)	0.49 [−0.04, 0.81]
Artic accuracy	0.95 (0.92–0.98)	0.99 [0.99, 1.00]	0.89 (0.78–0.98)	0.99 [0.97, 1.00]
Prosody	0.96 (0.75–1.00)	0.73 [0.35, 0.91]	0.83 (0.75–0.96)	0.0 [−0.55, 0.55]
Consistency	0.92 (0.82–0.96)	0.98 [0.90, 0.99]	0.83 (0.66–0.88)	0.92 [0.77, 0.98]

ICC: intra-class correlation coefficient; CI: 95% Confidence interval.

Table 4. Estimates of discrimination ability of DYMTA-A and DYMTA-B total scores and subscores.

Measure	AUC (95% CI)	Cutoff based on LR+	LR+/LR− (based on LR+)	Sensitivity/specificity based on LR+	Specificity at 90% sensitivity
DYMTA-A
Total score	0.92 [0.82, 0.98]	352.5	8.73/0.30	0.73/0.92	0.67
Vowel accuracy	0.89 [0.80, 0.97]	105.5	8.36/0.33	0.70/0.92	0.75
Artic accuracy	0.90 [0.80, 0.98]	173.0	8.36/0.33	0.92/0.67	0.91
Prosody	0.60 [0.47, 0.74]	20.5	3.64/0.76	0.30/0.92	–
Consistency	0.91 [0.81, 0.98]	47.5	8.73/0.30	0.73/0.92	0.50
DYMTA-B
Total score	0.94 [0.86, 0.99]	328.5	10.18/0.17	0.85/0.92	0.67
Vowel accuracy	0.89 [0.79, 0.97]	125.0	9.45/0.23	0.79/0.92	0.42
Artic accuracy	0.92 [0.82, 0.98]	125.5	9.09/0.26	0.76/0.92	0.67
Prosody	0.73 [0.56, 0.88]	19.5	4.73/0.66	0.39/0.92	0.50
Consistency	0.86 [0.71, 0.97]	55.5	4.73/0.25	0.79/0.83	0.58

AUC: area under the receiver operating characteristic curve; LR+: likelihood ratio for a positive test result; LR−: likelihood ratio for a negative test result. For Prosody subscore in DYMTA-A no reliable cutoff that produced 90 % sensitivity could be produced and thus specificity at such a cutoff could not be estimated.