Travel itinerary time-zone normalization errors: a source-led review

Research standards

Every review freezes its observation window before findings are calculated. Reviewers retain a row-level evidence ledger with the original artifact reference, timestamp, responsible role, status at cutoff, correction history, denominator, exclusions, and unresolved cases. Ambiguous records are coded independently before reconciliation, and both readings remain visible until an accountable adjudicator applies a documented rule. Missing information is treated as unknown rather than silently classified as success or failure. Sensitivity checks remove major record classes in turn so a pattern that depends on one owner, channel, event type, or reporting cycle is disclosed instead of presented as stable. Elapsed time is not translated into labor, an association is not described as causation, and local observations are not converted into external benchmarks.

Interpretation begins with counterexamples and the cases still open at the cutoff. A formally complete record may lack usable evidence, while an authorized alternative path may achieve the intended outcome without matching the expected workflow. The review therefore states the strongest alternative explanation, identifies the additional artifact that could distinguish it from the preferred reading, and records what would reverse or retire the resulting operating rule. Comparisons use the same field definitions and equivalent work classes; a material change in coverage, tooling, policy, or sample composition creates a new baseline rather than a trend. Follow-up records name the decision taken, responsible owner, anticipated signal, review date, exception path, and evidence required before a stronger intervention can be justified.

Governance checks keep only information necessary for the research question. Sensitive content is replaced with a controlled reference whenever an authorized reviewer can reproduce the classification without holding a copy. Access boundaries, retention expectations, correction ownership, disputed-interpretation routes, duplicate handling, spanning-record rules, and cutoff treatment are documented before release. Absolute counts appear beside percentages, small samples avoid false precision, and every external statement links to a listed source without implying that the publication measured the local record set. The proposed action must be proportionate, reversible, and reviewable. If the available evidence cannot support it, the gap becomes an explicit evidence request rather than an assumption.