TABLE 3.

Reliability assessment of the visual semi-quantitative scale for muscle echogenicity.

	Images + clips (n = 100)		Images (n = 80)		Clips (n = 20)
	AA	PABAK	AA	PABAK	AA	PABAK
Inter-reliability assessment
Overall	0.68 [0.68–0.69]	0.58 [0.57–0.59]	0.69 [0.68–0.69]	0.58 [0.57–0.59]	0.67 [0.66–0.68]	0.55 [0.54–0.56]
Grade 0	0.66 [0.65–0.67]	0.43 [0.41–0.44]	0.67 [0.66–0.68]	0.42 [0.41–0.44]	0.61 [0.60–0.63]	0.20 [0.18–0.22]
Grade 1	0.60 [0.60–0.61]	0.24 [0.22–0.25]	0.60 [0.59–0.61]	0.21 [0.20–0.23]	0.61 [0.60–0.63]	0.29 [0.26–0.31]
Grade 2	0.64 [0.63–0.65]	0.23 [0.21–0.24]	0.64 [0.63–0.65]	0.22 [0.21–0.24]	0.65 [0.63–0.66]	0.39 [0.37–0.41]
Grade 3	0.82 [0.81–0.83]	0.37 [0.35–0.40]	0.83 [0.82–0.84]	0.39 [0.37–0.42]	0.78 [0.76–0.80]	0.10 [0.08–0.12]
Intra-reliability assessment
Overall	0.78 [0.76–0.80]	0.71 [0.68–0.73]	0.78 [0.76–0.80]	0.70 [0.67–0.73]	0.76 [0.69–0.81]	0.67 [0.60–0.74]
Grade 0	0.78 [0.74–0.82]	0.69 [0.63–0.74]	0.77 [0.73–0.81]	0.67 [0.61–0.74]	0.75 [0.69–0.81]	0.61 [0.50–0.71]
Grade 1	0.59 [0.51–0.66]	0.47 [0.39–0.56]	0.56 [0.48–0.63]	0.42 [0.33–0.51]	0.74 [0.65–0.82]	0.65 [0.54–0.75]
Grade 2	0.55 [0.47–0.64]	0.44 [0.34–0.53]	0.55 [0.46–0.63]	0.42 [0.32–0.52]	0.68 [0.61–0.75]	0.52 [0.41–0.62]
Grade 3	0.68 [0.55–0.79]	0.63 [0.51–0.75]	0.71 [0.59–0.82]	0.66 [0.54–0.78]	0.70 [0.59–0.79]	0.61 [0.48–0.75]

AA, absolute agreement; PABAK, prevalence-adjusted, bias-adjusted kappa.

Values in square brackets are the 95% confidence intervals.