TABLE 1.

Demographic Characteristics for Both Anti-MDA-5 Antibody-Positive and -Negative Patients, Previous Reports

Reference	Study Type	Population Demographic	Population Studied	Total Patients Studied	Total Patients With DM or CADM	Anti-MDA-5-Positive Patients						MDA-5-Negative Patients
						No. Patients With MDA-5 (M/F)	Age at Onset (yr) (mean ± SD)	% With CADM or DM (CADM Only)	Deaths (%)	% With ILD	% With ILD and A/SIP	% With ILD and A/SIP
18	Cross-sectional	Korean	DM and PM	49	38	9 (4/5)	45.8 ± 16	100 (NA)	33	66	66	NA
10	Case report	Japanese	MDA-5	2	2	2 (0/2)	47.5 ± 24.7	NA	50	100	100	NA
7	Case series	American	DM	77	77	10 (3/7)	51.5 ± 8.8	NA	NA	60	22	5
32	Cross-sectional	Japanese	DM with ILD	25	25	12 (4/8)	53.5 ± 9.4	100 (50)	58	100*	42	8
28	Cross-sectional	Japanese	DM, CTD, IPF, healthy controls	294†	67†	27†‡ (NA)	NA	100 (92)	NA	NA	NA	NA
27	Nested case-control	Japanese	DM, CTD, IPF, healthy controls	255†	42†	8† (2/6)	44.5 ± 12.7	100 (100)	NA	88	50	NA
13	Multicenter cross-sectional	Japanese	DM, CTD	376†	376†	43† (9/34)	53 ± NA	100 (77)	44	93	NA	NA
23	Case series	Japanese	DM, CTD	192	13	13 (3/10)	57.3 ± 9.4	100 (84)	46	92	54	4
11	Case series	Japanese	DM	65	65	14 (3/11)	43.6 ± 14.6	100 (53)	63	100*	71	NA
15	Case series	Japanese	DM, CTD, SSc with ILD	135	82	21 (4/17)	47 ± 15	95 (91)	14	95	79	NA
8	Cross-sectional	Japanese	DM	30†	30†	8† (1/7)	60.5 ± 10.9	100 (75)	75	100	100	20

Abbreviations: A/SIP = acute or subacute interstitial pneumonitis, CTD = connective tissue disease, IPF = idiopathic pulmonary fibrosis, NA = not available; PM = polymyositis, SD = standard deviation, SSc = systemic sclerosis/scleroderma.

^*All patients had ILD as part of the inclusion criteria.

^†Indicates possible duplication of patients between studies.

^‡Number of patients with positive result by immunoprecipitation.