The application of scientific knowledge and methodology to legal problems and criminal investigations. Sometimes called simply forensics, forensic science encompasses many different fields of science, including anthropology, biology, chemistry, engineering, genetics, medicine, pathology, phonetics, psychiatry, and toxicology. The related term criminalistics refers more specifically to the scientific collection and analysis of physical evidence in criminal cases. This includes the analysis of many kinds of materials, including blood, fibers, bullets, and fingerprints. Many law enforcement agencies operate crime labs that perform scientific studies of evidence. The largest of these labs is run by the Federal Bureau of Investigation. Review articles are the summary of current state of understanding on a particular research topic. They analyze or discuss research previously published by scientist and academicians rather than reporting novel research results. Review article comes in the form of systematic reviews and literature reviews and are a form of secondary literature. Systematic reviews determine an objective list of criteria, and find all previously published original research papers that meet the criteria. They then compare the results presented in these papers. Literature reviews, by contrast, provide a summary of what the authors believe are the best and most relevant prior publications.