Table 2.

Intra- and inter-rater reliability of ultrasound muscle thickness measurements.

	Intra-rater ICC (95% CI)	Intra-rater SEM (mm)	Intra-rater MDC (mm)	Inter-rater ICC (95% CI)	Inter-rater SEM (mm)	Inter-rater MDC (mm)
Upper masseter (relaxation)	0.86 (0.68 to 0.94)	0.66	1.84	0.89 (0.74 to 0.95)	0.56	1.55
Upper masseter (clenching)	0.88 (0.71 to 0.95)	0.65	1.81	0.80 (0.56 to 0.92)	0.78	2.17
Upper masseter (maximal opening)	0.73 (0.43 to 0.88)	1.03	2.85	0.78 (0.52 to 0.91)	0.94	2.62
Middle masseter (relaxation)	0.82 (0.61 to 0.93)	0.86	2.39	0.71 (0.40 to 0.87)	0.99	2.74
Middle masseter (clenching)	0.83 (0.62 to 0.93)	0.89	2.47	0.77 (0.50 to 0.90)	0.95	2.64
Middle masseter (maximal opening)	0.85 (0.65 to 0.94)	0.87	2.41	0.85 (0.655 to 0.94)	0.94	2.61
Lower masseter (relaxation)	0.75 (0.47 to 0.89)	1.29	3.59	0.81 (0.58 to 0.92)	1.44	3.98
Lower masseter (clenching)	0.69 (0.36 to 0.86)	1.49	4.13	0.71 (0.40 to 0.87)	1.39	3.85
Lower masseter (maximal opening)	0.84 (0.64 to 0.93)	0.99	2.73	0.84 (0.65 to 0.94)	0.92	2.56
Temporalis (relaxation)	0.70 (0.38 to 0.87)	0.41	1.13	0.78 (0.52 to 0.91)	0.44	1.23
Temporalis (clenching)	0.75 (0.47 to 0.89)	0.35	0.97	0.79 (0.54 to 0.91)	0.42	1.16
Temporalis (maximal opening)	0.79 (0.54 to 0.91)	0.31	0.85	0.76 (0.49 to 0.90)	0.50	1.38
Lateral pterygoid (maximal opening)	0.63 (0.28 to 0.84)	0.58	1.62	0.75 (0.47 to 0.89)	0.49	1.36

ICC intra-class correlation coefficient, SEM standard error of measurement, MDC minimal detectable change.