The Evaluation of Clinical Responsiveness Using the Cutaneous Dermatomyositis Disease Area and Severity Index (CDASI), established in 2008, is a one-site database study conducted at the University of Pennsylvania. The database has yielded valuable information and clinical insights into the pathophysiology, disease processes, including psychological responses, treatments and quality of life associated with dermatomyositis. The CDASI database incorporates the Cutaneous Dermatomyositis Disease Area and Severity Index), a validated outcome measure of disease responsiveness in patients, and other assessment tools, surveys and patient information to help validate the clinical course and quality of life of patients with dermatomyositis. The CDASI database has led to publication of comparison studies of CDASI and other clinical instruments and the effect of dermatomyositis on Quality of Life (QoL). The CDASI database is an ongoing resource that enables clinicians to evaluate the evolving clinical changes, treatment modalities and patient response to a challenging disease. Data will be analysed over a 5 years.