Proportions of patients meeting definitions for progressive disease or improvement should be included in clinical trials for systemic sclerosis interstitial lung disease

shared decision-making, and facilitate real-world translation of clinical trial findings.Although the prevention of spirometric decline, as measured by the differences of mean changes in pulmonary function measures, may for now continue to be the primary endpoint of clinical trials, we suggest that an assessment of binary outcome data be included in all such trials as key secondary outcomes.Immunosuppressive or anti-fibrotic medications are now commonly recommended for the treatment of SSc-ILD based on RCT evidence of efficacy [5].However, not all patients will experience a decrease in FVC during the trials and therefore the question that requires addressing is what are the chances that any particular patient will obtain any benefit.Although our ability to predict decline in individual patients is very limited [16], from RCT data it is possible to derive an expected progression rate from the control group that would apply to any patient that meets the entry criteria for the study.Although this data is not perfect, it is the best we have and could be used to develop NNT data.To contextualize our editorial, we have summarized the SSc-ILD landmark trials to date in Table 1.The majority of these studies included SSc patients early in their