Where does fact-check get information on a product to make a decision on its effectiveness and safety?

1. Primary documents and the manufacturer’s own claims

The first port of call is the product’s own documentation: marketing claims, specifications, technical datasheets, user manuals, and — when applicable — regulatory submissions such as FDA or other filings; fact-checkers compare those claims against the underlying documents rather than accepting promotional language at face value ^{[2] [1]}.

2. Regulatory filings, recall databases and safety agencies

Government agencies and their published safety resources provide hard data on hazards, recalls and compliance; organizations like the U.S. Consumer Product Safety Commission publish fact sheets and incident statistics that fact-checkers use to assess risk and historical performance of product classes ^[5], and fact-checking teams routinely rely on federal and state raw datasets for verification ^[1].

3. Independent testing and lab reports

Independent test results—from accredited labs, consumer-test organizations, and investigative journalism labs—are essential when manufacturer claims hinge on performance or safety; rigorous fact-check protocols demand access to methodology and test data so conclusions can be reproduced or challenged ^{[3] [2]}.

4. Scientific literature, clinical trials and expert consultation

For medical devices, supplements, or health-related products, the evidence base in peer-reviewed research, clinical-trial registries, and domain experts is decisive; fact-checkers look for up-to-date, reproducible studies and consult qualified specialists to interpret complexity and to avoid oversimplification of experimental therapies ^{[3] [6] [7]}.

5. Prior reporting, databases and claim origin tracing

Fact-checkers perform “lateral reading” and search for prior work—other fact-checks, databases, and traceable origins of a claim—to avoid reinventing verification and to locate authoritative primary sources quickly; checking whether someone already evaluated the claim is a standard early move ^{[8] [4] [9]}.

6. Digital tools, algorithmic aids and manual oversight

Automated tools—Google’s Fact Check tools and other verification toolboxes—help locate prior evaluations and archived content, but fact-checking relies on human judgment to compensate for algorithmic gaps and evolving misinformation formats like deepfakes ^{[10] [11]}; the limits of automated detection mean newsroom processes still prioritize human-led source vetting ^[11].

7. Editorial workflows, documentation and transparency

Professional fact-checking follows structured workflows: annotating drafts, citing every source (contacts, transcripts, studies, screenshots), and line-by-line verification so any claim about safety or efficacy can be retraced to the supporting evidence; this practice is especially strict where public harm is possible, such as medical or diet claims ^{[3] [7]}.

8. How fact-checkers weigh conflicting evidence and uncertainty

When studies conflict or manufacturers cite unpublished data, fact-checkers present the weight of evidence, flag methodological weaknesses, and note uncertainty rather than delivering a binary verdict; meta-analyses and systematic reviews are used where available to reduce bias, and the timing and framing of corrections is informed by research on effectiveness of debunking ^{[12] [11]}.

9. Limits, agendas and source scrutiny

Fact-checkers scrutinize potential conflicts of interest—industry-funded studies, advocacy groups with a stake, or platforms that amplify particular outlets—and disclose these when relevant, because source selection and platform incentives can skew what evidence is available or prominent ^{[1] [13]}.