Patient selection: systemic sclerosis
Prevalence of ILD: 52%
Parameters:
(1) clinical findings on chest exam
(2) finding on chest imaging studies
(3) forced vital capacity (FVC)
(4) ratio of FEV1 to FVC
Decision rule 1: SSc-ILD is present if one or both of the following are present:
(1) typical basilar Velcro-like crackles on lung ausculatation
(2) presence of increased interstitial markings on chest X-ray AND absence of other explanation (congestive hart failure, pulmonary fibrosis, etc)
Decision rule 2: SSc-ILD is present if both of the following are present:
(1) FVC is < 70% of predicted
(2) ratio of FEV1 to FVC is > 70%
Decision rule 3: SSc-ILD is present if both of the following are present:
(1) FVC is < 80% of predicted
(2) ratio of FEV1 to FVC is > 70%
