Methodology

Evidence tiers

Evidence is shown on a visible seven-tier scale (1 = healthy-aging human lifespan RCT, down to 7 = in vitro/mechanism) and is never collapsed into a single marketing score. Tier 1 is empty on this site by design: no mitochondrial intervention has a healthy-aging lifespan RCT. Note the deliberate distinction between tier 2 (a human clinical-outcome RCT in a disease population, e.g. CoQ10 mortality in heart failure) and a healthy-aging lifespan result — the former is real and important, but it is disease treatment, not evidence of an anti-aging effect.

Honesty flag

Each intervention carries a flag derived by string classification of its human-evidence field: ● available is reserved for a genuine healthy-aging human lifespan RCT; ▲ qualified marks human data that is functional, biomarker, disease-outcome, failed, ongoing, or rare-disease grade — i.e. not a healthy-aging lifespan RCT; ○ none marks animal/preclinical-only, thin, or mechanism nodes. The classifier generalizes across the longevity cluster with zero data fabrication.

How identifiers are confirmed

Journal, volume and DOI were confirmed via Crossref, and trial design and status via the ClinicalTrials.gov v2 API where an NCT was resolvable. Each record states, per identifier, whether it is confirmed, not applicable to that study type, reported but not independently checked, or simply not confirmed. No identifier is invented and none is taken from a secondary source.

Record-level and identifier-level verification are kept apart. A study whose DOI is confirmed is a verified record even if its PMID has never been looked up — those are two different facts. Until 2026-08-08 both sat in one field on this site, so eleven records with confirmed DOIs displayed a badge saying their primary source was still outstanding.