TABLE 3

Univariable logistic regression for connective tissue disease associated interstitial lung disease (CTD-ILD) diagnosis

	Unadjusted OR	95% CI	p-value	AUC
Nailfold characteristics
Density <6/mm	7.47	2.73–20.43	<0.001^#	0.72
Giant ≥3 total	6.77	2.43–18.81	<0.001^#	0.70
Avascular ≥2 total	5.44	2.02–14.68	0.001^#	0.68
Microhaemorrhages ≥1 total	5.00	1.08–23.18	0.040^#	0.61
Baseline characteristics
Age	0.94	0.89–0.98	0.005^#	0.70
Male	0.18	0.06–0.47	0.001	0.70
Smoking	0.31	0.12–0.79	0.014	0.64
FVC % predicted	1.01	0.99–1.04	0.279	0.59
D_LCO % predicted	1.03	1.00–1.06	0.032	0.64
Clinical CTD manifestations
Any CTD manifestation^¶	42.18	10.80–164.74	<0.001^#	0.86
Serology and radiology
ANA ≥1:320	3.80	1.42–10.14	0.008	0.64
Positive ENA	5.38	2.04–14.20	0.001^#	0.68
Any myositis autoantibody⁺	0.33	0.10–1.05	0.061	0.60
Radiological NSIP, OP or NSIP/OP	7.48	2.33–23.93	0.001^#	0.71

Odds ratios (OR) are shown for the bivariate relationship of each variable with CTD-ILD diagnosis. FVC %: percentage predicted forced vital capacity; D_LCO %: percentage predicted diffusing capacity for carbon monoxide; ANA: antinuclear antibodies; ENA: extractable nuclear antibodies; NSIP: nonspecific interstitial pneumonia pattern on radiology; OP: organising pneumonia pattern on radiology; ^#: remains significant adjusted for age, sex, smoking, FVC%, treatment and pulmonary hypertension; ^¶: including any of inflammatory arthritis, Raynaud's phenomenon, digital oedema, palmar telangiectasia, digital tip ulceration, mechanic's hands, Gottron's papules/sign, sclerodactyly; ⁺: patients with positive myositis autoantibody and no clinical features of myositis classified as IPAF (non-CTD-ILD).