Table 2

Association of myositis-specific antibodies with clinical phenotype in patients with IIM

Phenotype	Marker	Alphadia					Euroimmun					Trinity
		Pos	Pos	Neg	Neg	P value	Pos	Pos	Neg	Neg	P value	Pos	Pos	Neg	Neg	P value
		Pos	Neg	Pos	Neg	P value	Pos	Neg	Pos	Neg	P value	Pos	Neg	Pos	Neg	P value
Malignancy	Tif1-γ	1	2	10	131	0.2135	3	14	8	119	0.1240	4	12	7	121	0.0212
Malignancy	NXP-2 (MORC3)	2	6	9	127	0.1155	1	4	10	129	0.3318	1	6	10	127	0.4337
DM skin lesions	Mi-2	6	2	53	83	0.0638	6	5	53	80	0.3582	5	4	54	81	0.4873
	TIF-γ	3	0	56	85	0.0667	16	1	43	84	<0.0001	14	2	45	83	<0.0001
	NXP-2 (MORC3)	4	4	55	81	0.7166	3	2	56	83	0.4003	4	3	55	82	0.4449
	MDA-5	5	2	54	83	0.1228	8	2	51	83	0.0159	6	4	53	81	0.3176
	SAE	4	1	55	84	0.1590	4	0	55	85	0.0265	4	2	55	83	0.2273
Amyopathic DM	MDA-5	2	5	5	132	0.0380	2	8	5	129	0.0758	2	8	5	129	0.0758
Calcinosis	NXP-2 (MORC3)	2	6	7	129	0.0801	2	3	7	132	0.0316	7	5	2	130	<0.0001
Inclusion body myositis	CN-1A											1	18	5	120	0.5791
Arthritis	Jo-1	14	17	10	103	<0.0001	13	16	11	104	<0.0001	10	14	14	106	0.0003
Arthritis	Jo-1, PL7, PL12 or EJ	16	21	8	99	<0.0001	16	21	8	99	0.0001	12	18	12	102	0.0004
ILD	Jo-1	19	12	13	98	<0.0001	19	10	13	100	<0.0001	15	9	17	101	<0.0001
ILD	Jo-1, PL7, PL12 or EJ	22	15	10	95	<0.0001	23	17	9	93	<0.0001	17	13	15	97 97	<0.0001
Raynaud	Jo-1	12	18	13	99	0.0003	13	15	12	102	<0.0001	9	14	16	103	0.0063
Raynaud	Jo-1, PL7, PL12 or EJ	16	20	9	97	<0.0001	17	22	8	95	<0.0001	11	18	14	99	0.0013

The association was evaluated by χ² testing or Fisher’s exact test (if cell size was <10) using Analyse-it for Excel.
IIM, inflammatory myopathy.