Table 3.

Summary of physiological measures of swallowing, calculated at the bolus level based on the first swallow per trial.

Parameter	Unit of measure	IDDSI level	ALS mean (95% CI)	Ref data mean (thin boluses) c (95% CI)	Interpretation for individuals with ALS	p value
Time-to-LVC a	ms	Thin	298 [260, 337]	179 [69, 148]	LVC occurred later	< .001
		Slightly	272 [224, 319]
		Mildly	296 [253, 339]
		Moderately	321 [277, 366]
		Extremely	331 [288, 373]
LVCdur a	ms	Thin	526 [471, 581]	436 [412, 460]	LVC closed longer	.004
		Slightly	485 [445, 526]
		Mildly	463 [426, 500]
		Moderately	440 [408, 472]
		Extremely	438 [402, 474]
UESOdur	ms	Thin	589 [555, 623]	458 [444, 472]	UES open longer	< .001
		Slightly	558 [527, 590]
		Mildly	583 [560, 606]
		Moderately	499 [480, 519]
		Extremely	486 [463, 509]
UESMax	%C2–4	Thin	16.6 [14.6, 18.6]	20.6 [19.3, 21.8]	UES opening narrower	.001
		Slightly	17.8 [15.7, 19.9]
		Mildly	18.5 [16.6, 20.4]
		Moderately	17.4 [15.7, 19.1]
		Extremely	20.0 [18.3, 21.8]
Max. pharyngeal constriction area b	%C2–42	Thin	1.8 (0;44.5)	0 (0;7.0)	Pharynx less constricted	< .001
		Slightly	2.3 (0;54.8)
		Mildly	2.2 (0;18.2)
		Moderately	2.4 (0;18.2)
		Extremely	1.6 (0;18.3)
LVC	Nominal grading; shown as % of bolus trials with partial or incomplete LVC	Thin	24%	< 1%	LVC more frequently not complete	< .001
		Slightly	27%
		Mildly	22%
		Moderately	11%
		Extremely	2%

Note. Results from thin liquid trials compared to a published healthy data (Steele, Peladeau-Pigeon, Barbon, Guida, Namasivayam-MacDonald, et al., 2019) set using unpaired t tests. IDDSI = International Dysphagia Diet Standardisation Initiative; ALS = amyotrophic lateral sclerosis; CI = confidence interval; LVC = laryngeal vestibule closure; LVCdur = duration of laryngeal vestibule closure; UESOdur = UES opening duration; UES = upper esophageal sphincter UESmax = UES opening diameter.

^a Based on swallows with complete LVC only.

^b Maximum pharyngeal constriction area reported using median (min;max) due to significant positive skew and presence of statistical outliers in the data.

^c Reference values reprinted from Steele, Peladeau-Pigeon, Barbon, Guida, Namasivayam-MacDonald, et al. (2019) reference article, with permission.