How should a systematic review report a search that was rerun after the original cutoff date?

Report the rerun as a separate search run with its own date, query, sources, filters, and added record counts, so readers can trace how the update changed the included evidence set. PRISMA 2020 calls for transparent reporting of the review's methods and of what studies were found and included, and the Cochrane Handbook describes documenting searches and managing records as part of the review process. Keeping each run distinct supports both aims.

What to record for each run

1. Label the run. Mark the original search and the update search as separate entries, each with the date it was executed. This preserves the original cutoff date alongside the later one.
2. Record the query and sources. For each run, note the search strategy and the sources searched, following the Cochrane Handbook's guidance on documenting searches. If the strategy changed between runs, record the revised version with the run it belongs to.
3. Record the filters. Note any limits or filters applied in each run, such as date limits or other restrictions, so a reader can see whether the update used the same constraints as the original.
4. Report added records. State how many records the update run added, keeping that count attached to the run that produced it.
5. Show the effect on the included set. Indicate which records from the update entered screening and which were ultimately included, so the change to the evidence set is visible.

Why separate runs matter

A rerun after the cutoff date changes the evidence base, and a combined total hides when and how that change occurred. Separate entries let a reader reconstruct the original search, the update search, and the difference between them. PubMed's Advanced Search and saved searches can help you re-execute and refine a documented strategy when you rerun it, and its field tags and filters let you record the specific constraints used.

Presentation

A table with one row per run and columns for date, query, sources, filters, and added records keeps the runs comparable at a glance. Pair it with the PRISMA 2020 flow diagram so the counts of records identified, screened, and included connect to the run that produced them.