Repair the foundations
First, document source coverage. Second, normalize or explain timestamps. Third, identify duplicate records. Fourth, check stable IDs and broken joins. Preserve an audit trail so repairs can be reviewed rather than silently changing source history.
Improve evidence
Fifth, locate missing outcome records. Sixth, document field meanings, transformations and exclusions in a versioned manifest. Seventh, rerun scoped checks on the proposed release, including after privacy transformations.
Know when to stop
Some gaps cannot be repaired because source records were deleted or permission is unavailable. Disclose those limits. Do not invent outcomes, synthesize undocumented history or label a dataset “verified” merely because a checklist has been completed.
Practical guidance, not legal advice or a buyer specification. Examples are illustrative. Reviewed October 20, 2026.