Not all evidence answers the same question. HealthspanDog separates evidence by what was studied, in which species and population, at what amount and duration, and with which outcome.
Evidence levels we distinguish
Finished-product canine evidence
Research on the exact finished product is the closest match to claims about that product. We record study design, dog population, sample size, comparator, duration, outcomes, adverse events, funding, conflicts, and whether the sold formula matches the studied formula.
Ingredient-specific canine evidence
Canine research on an ingredient can inform an ingredient discussion, but it does not automatically prove that every product containing that ingredient works. Form, processing, amount, combination, population, and endpoint still need to match.
Veterinary guidance and regulatory sources
Consensus guidance, official safety communications, labeling rules, and regulatory records help establish standard care, risk, and what a claim or label does—and does not—mean. These sources may not test product efficacy.
Other-species and human evidence
Human or other-animal research can generate hypotheses. It is not treated as direct evidence that a dog product produces the same outcome.
Laboratory and mechanistic evidence
Cell, tissue, chemical, and proposed biological-mechanism findings can explain why a question is worth studying. They cannot by themselves establish a real-world benefit, dose, safety profile, or lifespan effect in dogs.
Product and label records
For dated product records we aim to capture:
- Exact ingredient names, forms, and disclosed amounts.
- Serving basis and dog-weight bands.
- Package duration and cost per day.
- Labeled species, life stage, warnings, and storage directions.
- Product-specific studies and whether the current formula matches.
- Testing and certificate-of-analysis availability.
- Manufacturing or quality claims and the evidence supplied for them.
- Price, recurring terms, guarantee, and the date checked.
- Source URL, source type, access date, reviewer, and correction status.
Every material field is labeled brand claimed, independently verified, not disclosed, not found, or not applicable. We do not fill an unknown field by inference.
What common claims actually establish
Terms such as “clinically studied,” “vet formulated,” “third-party tested,” “human grade,” and “premium” vary in meaning. We look for the exact product or material studied, the professional’s documented role, the named test and laboratory relationship, the specification tested, and the result. A phrase alone is not scored as proof of effectiveness.
Ratings and conclusions
HealthspanDog will not compress evidence into a simple score until the scoring rules, weighting, uncertainty, conflict handling, and update process are published and tested. Where evidence is incomplete or conflicting, we say so.
Lifespan and healthy-aging claims
A biomarker, mechanism, mobility change, or short-term outcome is not the same as extended lifespan. We keep healthy-aging support, disease outcomes, and lifespan conclusions separate.
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