LAUSR

Randomized controlled trials (RCTs) are regarded as the gold standard of evidence‐based medicine. However, the disadvantages of RCTs have been well‐documented for a lengthy period of time. Due to the carefully controlled conditions, a small group of patients is studied, resulting in a lack of external validity and generalizability. To address this issue, real‐world evidence (RWE) has grown in importance as a complement to randomized controlled trials (RCTs). We introduce and describe the databases used by RWE in this post. Applications of RWE are described in following aspects with examples of patients in the use of biological agents with skin diseases: (1) support the safety and efficacy outcomes of RCTs; (2) reveal real‐world situations of adverse event management; (3) optimal treatment plans; (4) treatment's real‐world cost burden. We also focus on its superiority of generalizability, external validity, and time and economic efficiencies as well as its deficiencies in data resources, study design, and statistical methodologies.