Guides
Source evaluation and claim mapping: a practical guide
Source evaluation guide for separating claims, finding original evidence, testing authority and independence, recording limits, and writing accurate conclusions.
What to take away
- Break a story into small, checkable claims before searching for sources.
- Match each claim to evidence that can establish that exact point.
- Trace summaries, screenshots, and quotations back to their earliest available record.
- Judge authority in relation to the question, not by title, design, or domain alone.
- Record uncertainty and contradiction instead of forcing a clean verdict.
News verification starts with a sentence, not a website. A source may be reliable about its own filing date and weak about a competitor's motives. A witness may know what happened in one room but not why a decision was made elsewhere. Treating an entire source as true or false hides those boundaries.
Photo and credit
The image documents a moment of news consumption. It does not show whether every printed report was accurate or how the readers understood it.
Turn the story into claims
Copy each material assertion into a claim ledger. Split compound sentences. "The city approved a $3 million contract on Tuesday after receiving one bid" contains at least four claims: the decision maker, amount, date, and number of bids. Each may require a different record.
Label the claim type:
| Type | What can test it |
|---|---|
| Event | Direct observation, recording, timestamped record |
| Identity | Official record, subject confirmation, reliable directory |
| Number | Dataset, filing, calculation, stated method |
| Cause | Evidence of timing, mechanism, alternatives, and attribution |
| Quotation | Full recording, transcript, or contemporaneous notes |
| Opinion | Accurate attribution, not a truth rating |
| Prediction | Named assumptions and a clear future condition |
This step prevents a document that proves one detail from being cited as support for the entire sentence.
Find the evidence chain
Search distinctive wording, names, dates, document titles, docket numbers, image captions, and quoted figures. When an article cites another article, keep moving toward the interview, filing, dataset, speech, or observation underneath it. Preserve every layer because the path may reveal that a number changed units or that a quotation lost a condition.
For each source, record creator, publisher, date, version, purpose, audience, method, access route, conflicts, and the claim it supports. Ask whether two apparent confirmations are independent. Ten pages repeating one press release still provide one evidence chain.
Judge fit, authority, and independence
Authority depends on the claim. A regulator can establish what it filed or enforced. A researcher can explain a method within the researcher's field. A participant can describe a personal experience. None automatically proves a broader causal claim.
The UNESCO journalism and disinformation handbook page presents a curriculum that covers information disorder, fact-checking, social verification, and journalism practice. It also explains why misinformation and disinformation are more precise than using "fake news" for every false or disputed statement. Intent is a separate claim and should not be assigned without evidence.
Check who funded or commissioned the information, who collected it, what was excluded, and whether the publisher can correct it. Independence does not mean a source has no interests. It means the reporter can identify those interests, test the evidence, and seek confirmation beyond the same chain.
Write only what the evidence earns
Use a simple status for every claim: confirmed, contradicted, unresolved, not checkable, or out of scope. A precise unresolved finding is stronger than a guess. If records disagree, name the records, dates, definitions, and response from the responsible party.
Before publication, read headline, deck, captions, chart labels, alerts, and social copy against the ledger. Promotional text often drops the limits preserved in the article. Save the final evidence set and note the access date so a later correction can be reconstructed.
Common questions
Is a primary source always best?
No. It may be closest to an event yet incomplete, self-interested, misunderstood, or altered. It still needs context and corroboration.
Do two sources confirm a claim?
Only if they provide relevant evidence and do not merely repeat the same origin.
Can opinion be fact-checked?
The judgment itself may not be checkable, but its quotation, attribution, stated basis, and embedded factual claims can be.
What if no source settles the point?
Report the limit. Explain what was checked, what conflicts, and what remains unknown.
In this guide
- How to check an unfamiliar online source before trusting a claimOnline source verification workflow for preserving a page, identifying its publisher, reading laterally, tracing evidence, comparing reports, and recording limits.
- Firsthand accounts, records, experts, and reports comparedEvidence source types compared by proximity, scope, independence, strengths, limits, and best uses for checking events, numbers, causes, and quotations.
- Source and claim verification checklistSource and claim verification checklist for scope, origin, authority, evidence, independence, quotations, numbers, conflicts, response, wording, and corrections.
- Common source-evaluation mistakes and how to fix themSource-evaluation mistakes with fixes for surface trust, authority mismatch, circular citations, weak corroboration, bad search habits, and overstated conclusions.