Imaging Registries and Single-Center Series

Randomized controlled trials are often regarded as the pinnacle of research designs, valued for their rigor and internal validity. However, their high costs and selected patient populations limit their applicability, and complementary study designs are needed to guide evidence. In the realm of cardiovascular imaging, research designs using single-center series and registries have contributed key foundational insights into diagnosis, resource use and cost patterns, and prognosis as derived from practical, "real-world" settings. This review highlights the strengths and limitations of these study designs, provides notable examples, and indicates future directions for research.