Evaluating sources

The sources you use when writing a scientific text (such as a thesis, paper, etc.) largely determine the quality of that text.

Before you use the sources you have found their relevance and scientific nature should be evaluated. In this Libguide we will offer you several methods and tools.

Even if you do all the checks on these pages there are no guarantees that the texts you will be reading are true, objective and unbiased. You will always have to pay close attention to the sources you use. And above all, always remain a critical reader.

For non-scientific sources (newspapers, blogs, websites etc.) and so-called grey literature (e.g. master theses, dissertations, reports, statistics, policy papers), pay close attention to:

1. the author or responsible organisation
   1. is the author well-known and what are her/his qualifications?.
2. the publication date or the date when the source was updated
   • is the website up to date and properly maintained?
3. the purpose of the source
   • What is the intention of the source (promoting products, influencing opinions)? What is the target group (scientists, a specific group (for example patients), the general public)? 
4. the quality of the source
   • look at the use of language, the level of argumentation (are facts, figures and claims sufficiently substantiated?) and the literature references

See to the information on evaluating websites or use the CRAPMAP to make sure that you can use a website as your source.

You can use non-scholarly sources:

• as object of research (eg how is something discussed in popular media)
• when scientific research is not yet available
• as primary source (archive records, letters, interviews, statistics, news items etc.), to be used as documentation or factual material
• as indication of social relevance
• as illustration to your subject

See also the  LibGuide on the use of Wikipedia in science.