Literature reviews (or review articles) are critical evaluations of material that has already been published. By organizing, integrating, and evaluating previously published material, authors of literature reviews consider the progress of research toward clarifying a problem.
Review articles are not primary sources since they review previously published material. They can be of great value for identifying potentially good primary sources, but they aren't primary themselves.
In the Sciences, primary sources are documents that provide full description of the original research. For example, a primary source would be a journal article where scientists describe their research on rhizosphere bacteria. A secondary source would be an article commenting on or analyzing the scientists' research on rhizosphere bacteria.
Examples:
Literature Review or review article, magazine article, news article, book, textbook, etc.
|
Primary |
Secondary | Tertiary | |
|---|---|---|---|
| Definition | Original documents created or experienced concurrently with the event being researched | Works that analyze, assess, or interpret a historical event, an era, or a phenomenon. Generally uses primary sources. | Sources that identify, locate, and synthesize primary AND secondary sources |
| Characteristics | First hand observations, contemporary accounts of the event. Viewpoint of the time | Interpretation of information, usually written well after an event. Offers reviews or critiques | Reference works, collections of lists of primary and secondary sources, finding tools for sources |
| Examples | Interviews, news, footage, data sets, original research, speeches, diaries, letters, creative works, photographs | Research studies, literary criticism, book reviews, biographies, textbooks | Encyclopedias, bibliographies, dictionaries, manuals, textbooks, fact books |