Evidence and review methodology

Source hierarchy

We prefer legislation, regulators, government departments, network and market bodies, official registers and original provider documentation. Reputable secondary sources can add context but do not replace an available primary source.

Evidence labels

• Verified reported: reproduced or summarised from an identified source.
• Modelled estimate: calculated from stated inputs and assumptions.
• Informed but unproven: plausible interpretation that needs validation.
• Conflicting evidence: reliable sources do not currently agree.

Review and freshness

Material guidance records its sources and review date. Time-sensitive matters such as schemes, deadlines and regulation require more frequent review. A review date means the page was checked; it does not guarantee that nothing changed afterwards.

Directory checks

Directory-checked means specified profile fields were compared with named public sources on a recorded date. It is not an endorsement, recommendation, service-quality guarantee or statement of regulatory approval.

Corrections

We assess reported errors against the strongest available evidence. Material corrections should record what changed and when; disagreement alone does not justify removing accurately sourced information.