OBJECTIVES. In a multi-centre study, we sought to determine whether extent of disease on high-resolution CT (HRCT) lung, reported using a simple grading system, is predictive of decline and mortality in SSc-related interstitial lung disease (SSc-ILD), independently of pulmonary function tests (PFTs) and other prognostic variables. METHODS. SSc patients with a baseline HRCT performed at the time of ILD diagnosis were identified. All HRCTs and PFTs performed during follow-up were retrieved. Demographic and disease-related data were prospectively collected. HRCTs were graded according to the percentage of lung disease: >20%: extensive; 20%) on HRCT at baseline, reported using a semi-quantitative grading system, is associated with a three-fold increased risk of deterioration or death in SSc-ILD, compared with limited disease. Serial PFTs are informative in follow-up of patients. ; Owen A. Moore, Nicole Goh, Tamera Corte, Hannah Rouse, Oliver Hennessy, Vivek Thakkar, Jillian Byron, Joanne Sahhar, Janet Roddy, Eli Gabbay, Peter Youssef, Peter Nash, Jane Zochling, Susanna M. Proudman, Wendy Stevens and Mandana Nikpour