What makes a good source? 5 tips to assess the reliability of sources.

Faye Turner

9 min Read Time | April 4th 2022

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Source Reliability

Checking the reliability of a source is a real critical thinking challenge.

It is very important that you take a critical look at all sources, especially when they come from companies’ websites or small newspapers, to avoid greenwashing and misinformation.

It breaks down into 6 pillars, with questions that you should ask yourself when assessing the source.

Ready to shift to critical thinking mode? Here are the 6 pillars:

Currency: is this information up to date?

As a rule of thumb, we always prefer recent data, up to a year or two maximum prior to publication. This is even more important for impact related to the company’s practices and products.

For instance, an analysis on waste diversion should look at the data from the company’s most recent report.

If the impact you examine happened several years ago but the evidence was only established recently (for instance, when a clear ruling has established the misdoings of a company 15 years ago), we can accept older sources.

Relevance: is this information useful to my analysis?

  • Does the information relate to your topic?

  • Does it directly support your analysis?

  • Who is the intended audience?

  • Is it using an appropriate information level (too elementary/too complex)?

Authority: can the author be trusted?

  • Who is the author/sponsor/source/published?

  • What are the author’s credentials?

  • What qualifies the author to write this information?

  • Is there contact information?

  • Does the URL reveal authorship?

Accuracy: is the content correct, reliable, and objective?

  • Where does the information come from?

  • Is it supported by evidence?

  • Has it been revised?

  • Is it similar to other information?

  • Bias-free? Emotion-free and nuanced?

  • Are there spelling or grammatical errors?

  • Is it overly subjective?

  • Does it stick to facts or includes an opinion piece?
Blog sources trust

Purpose: why does this information exist?

  • What is the purpose of this information?

  • Is it to inform, teach, sell, entertain, or persuade?

  • Is the point of view objective and impartial?

  • Are there political, ideological, cultural, religious, institutional, or personal biases?

Videos are accepted as a source, as long as they come from reliable sources.


1. Blakeslee, Sarah (2004). "The CRAAP Test". LOEX Quarterly. 31 (3).

2. Fielding, Jennifer A. (December 2019). "Rethinking CRAAP: Getting students thinking like fact-checkers in evaluating web sources". C&RL News. 80 (11): 620–622.

What about the language of the source?

We accept any sources which can be read in English.

This means that you can add non-English sources, provided they can be translated into English. Here is the how-to guide:

1. Open this link: http://itools.com/tool/google-...

1a. Add the URL of the web page you would like to translate. Select the correct recipient language, "From" (e.g., Spanish, Mandarin, Hindu…)

1b. Pick English as the target language, "To." The translated source will appear in a new window (example).

1c. Use the URL of this new window to add to your analysis.

Please note that this translation tool only accepts web pages, not PDFs.

You can also use the following tools:

2. https://www.onlinedoctranslator.com/en/translationform

3. https://www.i2ocr.com/

As Google translate does not translate pdf files over 10MB in size, and you want to translate a pdf, you can follow the steps below:

  • You can split the original files pdf using this or any other site like this. You have extracted info from page x&y of the original file. You should split the pdf and create a new file with pages x&y.
  • Once you split and create that file, you can use the Google translator. Click on the language you want to translate, e.g., Chinese to English.
    • Click on the documents section, paste the file you split, click on the translate button, and download the file, which will now be in a translated version.
    • Now, you have the pages x&y file in a translated form.
  • You can upload the file on your Google Drive and generate a URL link, or by using another online software, but you may find the Drive to be more convenient.
  • Since you have a translated pdf file pages that you have extracted the data from and the original file, add both the original file source with page number and the translated file's source in your IN's sentences extracted from these files.

Reviewers retain the right to refuse non-English sources if the translation is inappropriate.

How "open" does a source have to be?

We only accept open sources in impact analyses. What does this mean?

Sources need to be freely accessible without any restrictions. The reason is that readers and raters need to be able to read any sources documented in the analysis and confirm the cited information.

Many sources are open-sourced, such as Wikipedia, certain online newspapers like the Guardian, and data providers. However, some sites are not freely accessible, like The Financial Times. You need to pay to access their articles, so we do not accept them. Finally, some sites are semi-open: visitors get limited access (think Statista) or only up to a certain amount of visits (for example, the CDP). These sites can be accepted if the information is viewable by everyone; otherwise, they might be rejected. The decisions remain on Reviewers, depending on the situation.


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