Information Literacy
Source Credibility Assessment
Evaluate a source against a few key dimensions — authority, evidence, bias and currency — and read laterally to see what everyone else says about it.
Why source credibility matters
In an age of infinite information, the bottleneck isn't finding an answer — it's knowing which answers to trust. A confident, well-designed page can be completely wrong, and a plain one can be rigorously accurate. Credibility has to be assessed, not assumed.
The good news: you don't have to judge every source from scratch. A few consistent questions, plus one powerful habit — lateral reading — will catch most unreliable sources fast.
Core principles of source assessment
Authority & expertise
Who created this, and are they genuinely qualified in the relevant field? Look for credentials, affiliations and a track record.
Evidence & citations
Does the source back its claims with verifiable evidence and link to primary sources? Assertions without evidence are just opinions.
Bias & objectivity
What's the source's perspective, purpose or funding? Everyone has a viewpoint — the question is whether it's disclosed and whether it distorts the facts.
Currency & relevance
Is the information current enough for the topic, and does it actually address your specific question?
Essential fact-checking methods
Lateral reading
Instead of digging deeper into one page, open new tabs and see what other sources say about it. Read across, not just down.
Reverse image search
Check where an image really came from and whether it's being used out of its original context.
Source tracing
Follow claims back to their original source rather than trusting a summary of a summary of a summary.
Cross-reference verification
Confirm a claim appears in multiple independent, credible sources before you accept it.
Red flags to watch for
- Emotional language designed to provoke rather than inform.
- Missing sources, or a vague “studies show” with nothing to check.
- Fake or misrepresented experts speaking outside their field.
- Poor design, broken links, or a URL mimicking a real outlet.
- Circular references — sources that only cite each other.
- Claims that are simply too good (or too bad) to be true.
In short
A source's credibility isn't a yes/no verdict — it's a judgment across a few dimensions: who made it, what evidence backs it, whose interests it serves, and how current it is. The fastest habit is lateral reading: don't just study the page in front of you — open new tabs and see what everyone else says about it.