Good Practice for
Effective ISF Retention
Four Core Pillars
To ensure Investigator Site Files (ISFs) are preserved and compliant over the long term, embed retention practices early. Anchor your strategy on four core pillars. Data Safeguarding, Digital Preservation, Access & Consolidation, and Inspection Readiness, all aligned with regulatory expectations and practical needs.
1. Data Safeguarding
Why it matters:
ISFs must remain intact and complete throughout their required retention period. Sites face risks from physical damage (fires, floods) or data corruption.
What actions are needed:
- Check all data on entry using a “fixity check” – this ensures that all the data is healthy and is exactly the same as it was before transfer into the archive.
- Store a minimum of two copies of your data in separate geographic locations. An optional third “Escrow” option provides extra safeguarding and protection if required.
- Automatically and regularly check (through more fixity checks) every file within the archive, to quickly identify any changes to your data, corruption or otherwise.
- Ensure a process is in place to replace any damaged or lost data, however it occurred, with a healthy copy from one of the other storage locations.
2. Digital Preservation
Why it matters:
ISFs must remain intact and complete throughout their required retention period. Sites face risks from physical damage (fires, floods) or dDigital ISFs must be it every possible chance of being usable, legible and readable both now and in the future, despite evolving technology. Hardware and software become obsolete, file formats change, and without proactive strategies, records risk becoming inaccessible.ata corruption.
What actions are needed:
- Apply ALCOA+ principles: Attributable, Legible, Contemporaneous, Original, Accurate, and importantly, Complete, Consistent, Enduring, and Available. These principles ensure records remain reliable over time.
- Use a risk-based preservation approach: identify which records are critical, assess the risk of format or storage obsolescence, and prioritise preservation efforts accordingly. Less critical records can adopt simpler retention methods.
- Maintain long-term preservation copies of data through a process called ‘file format normalisation’. In practice this means that our solution:
- Identifies what format the file is in.
- Automatically generates an associated long-term copy in line with digital preservation good practice, for example a Word Document will generate a PDF/A copy.
- Continues to review digital preservation trends and good practice throughout the entire lifecycle of the data, adjusting preservation processes if required.
3. Consolidation & Managing Access
Why it matters:
Data sprawl or duplicated ISFs creates risks of lost documents and inconsistent version control, complicating retrieval and compliance.
What actions are needed:
- Consolidate ISFs into a single digital archive at trial close-out. This simplifies retention, retrieval, and reduces sprawl.
- Ensure the repository supports consistent access controls, version history, and robust searchability.
- Maintain comprehensive metadata and inventories so each document’s context, location, and status remain easily discoverable. This also aligns with ICH E6(R3) requirements for document inventory and traceability.
4. Inspection Readiness & Audits
Why it matters:
ISFs must be ready for regulatory review at any time. Gaps or unclear records can lead to audit findings, delays, or compliance issues.
What actions are needed:
- Conduct regular audits throughout the trial to track completeness, detect gaps early, and reduce corrective work during inspections.
- Maintain intact audit trails, metadata, and version control to demonstrate governance and record integrity.
- Use systems capable of automated integrity reporting to confirm that records remain unmodified and accessible over time.
Overarching Approach
Across all pillars, a risk-based approach ensures resources focus on the most critical areas. As Sandra Blake from Barts Health NHS Trust highlighted during Arkivum’s ArkFest virtual conference, tailoring retention strategies based on the complexity and criticality of trial documentation allows organisations to manage long-term obligations efficiently and with confidence.