You will find two types of research articles in peer-reviewed science journals: primary and secondary.
Primary research articles describe original research written by the researcher(s) of the study. A research article explains the topic, purpose of the study, the demographics of the groups studied, how the study was conducted (methodology) and data collected, the results of the study and why the research is valuable. These include experiments, observations, case studies, and surveys. The following are examples of peer reviewed/refereed research articles:
Review Arizona State University's Ask A Biologist website to learn more about how to identify an original research article by its components.
Secondary research provides a summary and/or analysis of original scientific research. The most common type of secondary research articles are review articles (literature, systematic review, meta-analysis). These types of articles summarize a number of research studies in a particular area and provide analysis on the research as a whole.
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