Identifying and avoiding bias in research.

This narrative review provides an overview on the topic of bias as part of a series of articles in Plastic and Reconstructive Surgery on evidence-based medicine. Bias can occur in the planning, data collection, analysis, and publication phases of research. Understanding research bias allows readers to critically and independently review the scientific literature and avoid treatments that are suboptimal or potentially harmful. A thorough understanding of bias and how it affects study results is essential for the practice of evidence-based medicine.