Table 1.

Test characteristics

	IBM+RV vs PAM				IBM - RV vs PM&DM
Test feature	AUC	Cut-off (% of affected fibres)	Sensitivity	Specificity	AUC	Cut-off (% of affected fibres)	Sensitivity	Specificity
Rimmed vacuoles	0.60	>0.28	0.53	0.71	–	–	–	–
p62 aggregates	0.87	>0.48	0.87	0.86	0.60	>0.21	0.22	0.91
TDP-43 aggregates	0.80	>0.34	0.80	0.86	0.53	<0.01	0.89	0.18
Ubiquitin aggregates	0.68	>0.18	0.53	0.86	0.64	<0.01	1.00	0.27
Myotilin aggregates	0.55	<2.50	1.00	0.29	0.91	<0.01	1.00	0.82
Congophilic deposits	0.56	>0.24	0.73	0.71	0.56	>0.03	0.11	1.00
COX−/SDH+ fibres	0.87	>0.04	0.86	0.86	0.93	>0.1	0.78	0.91

AUC, area under the curve; COX, cytochrome oxidase; IBM, inclusion body myositis; PAM, protein accumulation myopathies with rimmed vacuoles; PM&DM, steroid-responsive inflammatory myopathies; RV, rimmed vacuoles; SDH, succinate dehydrogenase; TDP-43, transactivation response DNA binding protein-43.