Speech-Language Pathology

Many students may find useful this definition of primary sources: "Primary sources are those with a direct link, in time and place, to the person, event, situation, or culture under study." 

For example, a newspaper article on the outbreak of World War II in 1939 would be a primary source; a newspaper article reflecting on the outbreak of that war in 2014 would be considered a secondary source. A primary source, such Abraham Lincoln's "Emancipation Proclamation," issued January 1, 1863, is a primary source, but it is also a primary source when republished in 1963.

Primary:

• Consists of original studies conducted by the authors
• Includes: controlled trials, cohort studies, case studies
• Includes: methods, results, tables, figures

Secondary:

• Consists of assimilated evidence from a number of high quality primary studies
• Includes: systematic review, meta-analyses, evidence summaries
• May include: methods as a literature review, cited tables and results from other studies