Fact-Checking Policy
Last updated: August 2026
What counts as a fact
Not all product information is equal. We classify sources into three tiers:
Strong evidence
- Official manufacturer manuals and user guides
- Manufacturer-published specification sheets
- Official warranty documents and certification filings
Medium evidence
- Manufacturer product pages (can change without notice)
- Reputable retailers that reproduce manufacturer-confirmed data
- Independent testing by recognized organizations
Weak evidence
- Affiliate blogs that paraphrase other affiliate blogs
- Customer reviews and forum discussions
- Product listings on aggregator sites without stated sources
A claim repeated across ten blogs is not ten independent confirmations. If they all trace back to the same Amazon listing, it is one unverified source.
Duplicate-source detection
Before treating a claim as "confirmed by multiple sources," we check whether those sources are independent. Many affiliate sites copy specifications from each other or from the same retailer listing. A copied chain does not increase confidence — it just repeats the original source, which may itself be wrong.
We trace claims to their origin. If we cannot find an independent primary source, the claim stays at its original confidence level regardless of how many sites repeat it.
Research confidence model
Every product fact is assessed on four dimensions:
- Identity verified: we are confident the source refers to the exact product and model, not a similar one
- Primary source: the fact originates from the manufacturer or an authorized datasheet, not a third-party paraphrase
- Specs verified: we have confirmed the specific value against at least one strong or medium source
- Conflicts resolved: where sources disagree, we have investigated and documented which is correct
A fact meets our publication threshold when identity is verified and at least one strong or medium source supports it. If conflicts exist and cannot be resolved, we either note the discrepancy openly or omit the claim.
Claim verification states
Every factual claim in our articles is assigned one of these states internally:
| State | Meaning |
|---|---|
| supported_primary | Confirmed by a manufacturer manual, datasheet, or official spec sheet |
| supported_multiple | Confirmed by two or more independent sources (not copied from each other) |
| supported_attributed | Stated by one source, attributed explicitly — we tell you who says so |
| unsupported | We could not find a primary source; claim is weakened or removed |
| contradicted | Sources disagree and we could not resolve the conflict; noted in the article |
| unverifiable | No reliable source exists; claim is not published |
Conflict resolution
When sources disagree (e.g., Amazon listing says 8,000 Pa suction but the manual says 5,500 Pa):
- Verify exact model, variant, and revision
- Check manual revision dates — specs change between production runs
- Seek a second manufacturer source (official website, datasheet)
- If resolved: publish the verified value and note the discrepancy
- If unresolved: either note both values with sources, or omit the specification
We never pick whichever value is more convenient. See how we research for the full source hierarchy.
Material vs minor claims
We distinguish between claims that affect a buying decision and those that don't:
- Material claims — suction power, runtime, noise level, dimensions, navigation type, warranty. These must meet the publication threshold before we state them as fact.
- Minor claims — aesthetic details, accessory inclusions, marketing descriptions. These may be attributed to a single source if clearly labeled.
If we are unsure whether a claim is material, we treat it as material.
Corrections
When we get something wrong, we fix it and document the change. See our corrections page for the correction log and our error-reporting process.