Evidence Rating Legend

Every compound in this wiki carries an evidence_quality field in its frontmatter. Use this page to understand what each tier means before drawing conclusions.

Tiers

RCT — Randomized Controlled Trials

Multiple peer-reviewed, randomized, controlled trials have been conducted in humans. Results may be mixed or context-dependent, but the methodology is the most rigorous available. An RCT rating does not mean the compound always works; it means human-controlled evidence exists.

Examples in this wiki: Caffeine, Bacopa Monnieri, Creatine, Omega-3 Fish Oil, Magnesium, Ashwagandha, Racetams.

Observational — Human Observational / Epidemiological

Evidence comes from cohort studies, epidemiological surveys, or small open-label trials. Confounders are harder to control. Association does not imply causation, but the signal is meaningful when consistent across populations.

Examples in this wiki: Gotu Kola, Vinpocetine, Pantothenic Acid (B5), Resveratrol.

Preclinical — Animal Models and In Vitro

The mechanism is plausible and evidence exists in cell cultures or animal models, but controlled human trials are sparse or absent. Effects may not translate. Use these compounds with extra skepticism and lower expectations.

Examples in this wiki: Lions Mane (improving), Sulforaphane, PQQ, Bromantane, Dihexa, NSI-189, Epithalon, Pinealon.

Anecdotal — Community Reports Only

No meaningful controlled research in humans. Evidence is user self-report, forum data, or historical use. Mechanism may be proposed but not validated. Effects are highly variable.

Examples in this wiki: Phenibut (effects well known but not RCT-studied), GABA (poor CNS penetration debated), DMAE.

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Practical interpretation

A high evidence rating does not mean a compound is safe or useful for everyone. A low evidence rating does not mean it does not work. Match your willingness to experiment with your tolerance for uncertainty.

The evidence_quality field is a signal for how to weigh claims — not an endorsement or rejection of a compound.

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