Observational Comparative Research in Cardiovascular and Brain Health and Disease: A Scientific Statement From the American Heart Association

Target trial emulation is a useful framework to guide the design and illuminate the limitations of observational studies

A formal study protocol should be prepared before every observational study to enhance rigor, reduce data manipulation and promote transparent reporting

Choose the study data source early in design, based on concordance between the study question's needs and the data set's properties

Use causal directed acyclic graphs to specify exposure, end points, confounders, colliders, moderators and mediators