Source hierarchy
The right source depends on the claim. Regulatory status comes from the regulator; ingredients and directions from the current label; price and terms from the merchant; efficacy and safety from an appropriate body of scientific evidence; lived experience from clearly identified people without turning experience into proof.
Primary and authoritative sources
We prioritize peer-reviewed primary research, systematic reviews, public trial registries, official government material, recognized standards, professional guidance, recall databases, labels, and original records. Secondary reporting can provide context but does not replace the underlying record for a consequential claim.
Quality and relevance
Fact-checking asks whether the source studied the relevant population, product, dose, duration, comparison, and outcome; whether the design supports the type of conclusion; whether the result is meaningful; what conflicts exist; and how the finding sits within the total evidence.
Claim-level process
Material factual and health claims are recorded in a claim inventory with their exact language and citation. An editor checks the source directly, confirms that qualifications remain attached, verifies names, dates, units, prices, quotes, links, and disclosures, and routes specialized interpretation to the relevant reviewer.
Citation presentation
Citations appear close enough to the claim for a reader to understand what they support. We link to accessible primary records when possible, identify paywalled or retracted material, preserve retrieval dates for changing records, and do not use a long source list to make weak evidence look stronger.