Every claim should be traceable to its source, and every source should be verifiable. This page explains how PeptideScholar evaluates evidence, calculates trust scores, and keeps editorial standards explicit.
Each peptide receives an overall grade from A to D based on the quantity, quality, and consistency of published research. These grades are not recommendations for use. They reflect how much confidence the available literature supports.
Multiple high-quality randomized controlled trials or systematic reviews with consistent results. At least one large, well-powered trial. FDA approval typically falls in this category.
Semaglutide (STEP 1-5, SELECT), Tirzepatide (SURMOUNT-1, SURPASS-2), Teriparatide (FREEDOM trial)
Limited RCTs, a single large trial, or multiple smaller trials with some methodological limitations. Evidence is promising but not as robust as Grade A. May include Phase 2 data or well-designed cohort studies.
Retatrutide (Phase 2 data only), Bremelanotide (two Phase 3 trials), Tesamorelin (smaller RCTs)
Primarily preclinical data, case series, or small human pilot studies. Some human evidence exists but is insufficient for strong conclusions. No regulatory approval.
BPC-157 (animal studies only), TB-500 (preclinical), GHK-Cu (small cosmetic trials)
No human data. Evidence is limited to in vitro studies, theoretical mechanisms, or anecdotal reports. High uncertainty. Often includes research chemicals and novel compounds with minimal published literature.
FOXO4-DRI (mouse studies only), Dihexa (rodent models), P21 (no human trials)
The trust score shown on each peptide page is a 0-100 composite that gives readers a fast signal about how well supported a page is. It comes from four independent factors.
Peptide-level evidence grade contributes up to 40 points. Grade A peptides start at 40, B at 30, C at 20, and D at 10. This reflects the overall maturity of the compound's research portfolio.
We evaluate what percentage of individual benefit and side-effect claims have direct PubMed citations. Seventy-five percent or higher earns 30 points, 50 percent earns 20, and 25 percent earns 10.
The number and quality of cited studies matters. Peptides with five or more verified references earn 20 points, three or more earn 15, and one or more earns 10. Every PMID is verified against PubMed.
Every individual claim should carry an explicit evidence grade. When 100 percent of claims are graded, the peptide earns a 10-point bonus. This keeps reliability visible at the claim level.
Every benefit and side-effect claim on PeptideScholar is stored as a sourced claim that links text to specific PubMed IDs and an explicit evidence grade. That structure makes citations, verification, and claim-level reliability visible instead of implied.
We do not fabricate PMIDs. In April 2026, we removed 47 fabricated references and put automated verification in place to prevent recurrence. See the credibility changelog for the public record.
A peptide with Grade A evidence may still have meaningful side effects or be inappropriate for some people. A Grade D peptide is not automatically unsafe; it usually means the human evidence is missing.
Positive results are more likely to be published than null or negative results. The grades reflect the published literature, not the total universe of unpublished data.
PeptideScholar is an educational resource. Nothing on this site constitutes diagnosis, treatment, or personal medical guidance.