Europe
In January 2023 EMA published a new Q&A with a clarification of Day 0 in the context of local literature review when it concerns physical copies of journals.
Marketing authorisation holders (MAH) must review and assess reports of suspected adverse reactions from medical literature to identify and record individual case safety reports (ICSRs).
For ICSRs, described in the medical literature containing the minimum criteria, the clock starts (day zero) on the day when the physical/hard copy local journal is received by the organisation/Marketing authorisation holder/Applicant, and this should be considered equal to performing a literature search in an electronic database.
It is important to note that this affects the process only if you use physical copies of the journals, process for electronic databases remains the same.
Source: Coordination of pharmacovigilance inspections | European Medicines Agency (europa.eu)