Sourcing policy
Where Our Facts Come From: Our Sourcing and Citation Promise
Last updated November 2026
Last reviewed: November 4, 2026. This policy is owned by the ProGrade Research Desk.
Picture two headlines. "Compound X boosts muscle growth." And "Compound X boosted muscle growth in 12 rats." Only the second tells you what was found. This policy makes sure you always get the second kind.
On this page:
- Which sources we trust most, and which we never count
- How we label cell, animal and human findings
- Why no one can buy a citation from us
Which sources do we trust most?
Think of a courtroom. The original document beats someone's retelling of it. When sources disagree, the higher tier wins. When only a lower tier exists, we say so.
| Tier | Source type | Examples | How we use it |
|---|---|---|---|
| 1 | Regulatory and standards documents | FDA pages, guidance and warning letters; Federal Register; USP–NF chapters; WADA Prohibited List; EMA; ClinicalTrials.gov | The final word on legal, regulatory and testing facts. Always dated. |
| 2 | Peer-reviewed research | Systematic reviews and meta-analyses; randomized trials; observational studies; animal and cell studies (PubMed-indexed journals preferred) | The basis for every scientific claim, ranked by study design |
| 3 | Preprints | bioRxiv, medRxiv, arXiv | Only when nothing peer-reviewed exists. Always labeled "preprint, not peer-reviewed." Re-checked for a published version at each review. |
| 4 | Trusted news and trade reporting | Coverage of an event, such as an advisory committee vote | To report that an event happened. Paired with or replaced by the primary document once it's out. |
What don't we count as evidence?
- Seller marketing, including our own product copy
- Forums, social media, podcasts and influencers
- Personal stories and "it worked for me" posts
- AI summaries, including our own drafting tools
- Retracted studies
Independent lab tests crowdfunded by a community can be reported as just that, with the lab and date named. They're never the sole basis for a quality or safety claim.
How do we rank studies?
Within peer-reviewed research, our order runs strongest first:
- Systematic reviews and meta-analyses of controlled human trials
- Randomized controlled trials in people
- Non-randomized human studies, case series and case reports
- Animal studies
- Cell and tissue (lab-dish) studies
- Narrative reviews and expert opinion
For any one finding, we cite the original study, not a review that mentions it.
How do you know where a finding came from?
Most research-peptide evidence comes from cells and animals, not people. You should see that in every sentence, not in a footnote.
| Evidence came from | How we write it |
|---|---|
| Cells in a dish | "In cultured human fibroblasts..." |
| Animals | "In rat models...", "In a mouse study..." (species always named) |
| A human trial | "In a phase 2 trial of [n] participants..." (phase and size named) |
| Human records or case series | "In a retrospective case series of [n] patients..." |
| A mechanism or theory only | "Researchers propose...", with who proposed it |
The rules that go with the labels:
- No species jumps. An animal result is never rewritten as a human effect.
- No fragment jumps. Data on one molecule isn't applied to a related one without saying so. Example: a full protein versus a short synthetic piece of it.
- Single-lab research is flagged. When most of a compound's studies come from one group, we say so.
- Funding is flagged. If a company with a stake in the result ran or paid for a trial, we note it.
- No hedging instead of evidence. We cite a specific study for a claim, or we drop the claim.
Our rule: A rat result is never rewritten as a human result. Not in a headline, not in a summary, not anywhere.
How do we cite?
- Format: authors, year, title, journal, volume and pages, with a PMID or DOI link. Regulatory documents name the agency and date.
- Opened, not copied. Each reference is a source we opened. An unchecked reference is flagged and can't support a published claim.
- Dates on anything that changes. Legal and regulatory statements carry a "last checked" date.
- Our own data is labeled. When we cite a ProGrade certificate of analysis, we name the testing lab and lot number, and say it's our product.
Can anyone pay to be cited?
No. We take no money, free product, affiliate fees, co-marketing or other perks. That goes for citing, linking to or describing any study, lab, product or person.
Links to studies and regulators are never paid placements. If we do business with a group we cite, such as a lab that tests our lots, we say so next to the citation.
FAQ
Why do you say "in rats" so often?
Because most research-peptide findings come from animals. A rat result doesn't tell you what happens in people, so we always name the species.
Do you ever cite preprints?
Only when no peer-reviewed source exists. We label them "preprint, not peer-reviewed" and check for a published version at each review.
Do you cite your own lab reports?
Yes, clearly labeled, with the testing lab and lot number named.
What if I spot a bad citation?
Tell us. We handle it under our corrections policy.
Your next step
Spotted a citation that's wrong, outdated, retracted or misdescribed? Report it under our corrections policy.
Related: Editorial policy · How to read a certificate of analysis
For research use only. Not for human consumption. These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.
Research Use Only
All ProGrade Peptides products are sold strictly for laboratory and research use. They are not drugs, foods, cosmetics, or supplements, and are not intended to diagnose, treat, cure, or prevent any disease, nor for human or veterinary consumption. Purchasers confirm they are qualified researchers aged 21 or older.