|Epidemiology is the study of the circulation and patterns of health events, health characteristics and their origins or influences in clear populations. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive medicine. Pharmacoepidemilogy is a part of epidemiology since it deals with the effects of drugs in large numbers of people or in a population.
A journal is a periodical publication intended to further progress of science, usually by reporting new research. Most journals are highly specialized, although some of the oldest journals publish articles, reviews, editorials, short communications, letters, and scientific papers across a wide range of scientific fields. Journals contain articles that peer reviewed, in an attempt to ensure that articles meet the journal's standards of quality, and scientific validity. Each such journal article becomes part of the permanent scientific record.