01Available sources
Source hierarchy
We prioritize official records, regulatory documents, original studies and primary datasets. Reviews and institutional materials provide context. An automated summary is never used as a source.
02Available sources
Two separate checks
Provenance confirms the identity and existence of a document. Interpretation checks whether a statement preserves the population, method, period, geography and limitations. Checking a link does not complete scientific review.
03Available sources
Numbers in context
Estimates require a source, year, population, geography and denominator. We do not combine incompatible series or infer causality from association.