Table 2.

Inter-Rater Reliability of the mRUST Score, Overall and Stratified by Final Instrumentation, Defect Size, and Bone Grafting Status

	Not Used in KA and ICC		Used in KA and ICC
	0/3 scores*	1/3 scores*	2/3 scores*	3/3 scores*	KA (95% CI)	ICC (95% CI)
Overall	10 (5%)	21 (10%)	24 (11%)	158 (74%)	0.64 (0.54, 0.71)	0.71 (0.65, 0.77)
By Instrumentation
IMN	1 (1%)	4 (3%)	6 (5%)	104 (90%)	0.65 (0.53, 0.74)	0.75 (0.68, 0.81)
Plate	6 (25%)	8 (33%)	7 (29%)	3 (13%)	0.88 (0.60, 0.94)	0.90 (0.72, 0.97)
Ring	3 (10%)	8 (28%)	7 (24%)	11 (38%)	0.47 (0.13, 0.69)	0.62 (0.36, 0.83)
None	0 (0%)	1 (2%)	4 (9%)	40 (89%)	0.48 (0.28, 0.63)	0.57 (0.41, 0.72)
Defect Size (cm)
<2.5	5 (5%)	8 (7%)	9 (8%)	87 (80%)	0.60 (0.46, 0.71)	0.70 (0.61, 0.78)
2.5–5.0	3 (6%)	8 (15%)	6 (12%)	35 (67%)	0.77 (0.60, 0.85)	0.85 (0.77, 0.91)
>5.0	2 (4%)	5 (10%)	9 (17%)	36 (69%)	0.57 (0.36, 0.71)	0.67 (0.53, 0.79)
Grafted prior to X-ray?
No	3 (3%)	10 (10%)	10 (10%)	81 (78%)	0.61 (0.47, 0.72)	0.70 (0.61, 0.78)
Yes	7 (6%)	11 (10%)	14 (13%)	77 (71%)	0.66 (0.54, 0.75)	0.73 (0.64, 0.80)
Yes, days prior:
<30	0 (0%)	0 (0%)	1 (33%)	2 (67%)	—	—
30–90	0 (0%)	3 (21%)	1 (7%)	10 (71%)	0.60 (0.19, 0.79)	0.67 (0.31, 0.90)
>90	7 (8%)	8 (9%)	12 (13%)	65 (71%)	0.66 (0.52, 0.76)	0.74 (0.65, 0.82)

^*- the number of raters (0, 1, 2, or 3) out of 3 who provided an mRUST score for all 4 cortices of a given case.

KA indicates Krippendorff’s Alpha; ICC indicates Intraclass Correlation Coefficient.